diff --git a/cargo/lib/dependabot/cargo/update_checker/requirements_updater.rb b/cargo/lib/dependabot/cargo/update_checker/requirements_updater.rb
index b02a91eb70..2c08acd131 100644
--- a/cargo/lib/dependabot/cargo/update_checker/requirements_updater.rb
+++ b/cargo/lib/dependabot/cargo/update_checker/requirements_updater.rb
@@ -141,7 +141,11 @@ def update_range_requirements(string_reqs)
             raise UnfixableRequirement if req.start_with?(">")
 
             req.sub(VERSION_REGEX) do |old_version|
-              update_greatest_version(old_version, target_version)
+              if req.start_with?("<=")
+                target_version
+              else
+                update_greatest_version(old_version, target_version)
+              end
             end
           end.join(", ")
         rescue UnfixableRequirement
diff --git a/cargo/spec/dependabot/cargo/update_checker/requirements_updater_spec.rb b/cargo/spec/dependabot/cargo/update_checker/requirements_updater_spec.rb
index ad8c424cfd..267c17c038 100644
--- a/cargo/spec/dependabot/cargo/update_checker/requirements_updater_spec.rb
+++ b/cargo/spec/dependabot/cargo/update_checker/requirements_updater_spec.rb
@@ -168,20 +168,40 @@
         end
 
         context "when there were multiple range specifications" do
-          let(:req_string) { "> 1.0.0, < 1.2.0" }
+          context "with `less than`" do
+            let(:req_string) { "> 1.0.0, < 1.2.0" }
 
-          its([:requirement]) { is_expected.to eq("> 1.0.0, < 1.6.0") }
+            its([:requirement]) { is_expected.to eq("> 1.0.0, < 1.6.0") }
 
-          context "when already valid" do
-            let(:req_string) { "> 1.0.0, < 1.7.0" }
+            context "when already valid" do
+              let(:req_string) { "> 1.0.0, < 1.7.0" }
 
-            its([:requirement]) { is_expected.to eq(req_string) }
+              its([:requirement]) { is_expected.to eq(req_string) }
+            end
+
+            context "when including a pre-release" do
+              let(:req_string) { ">=1.2.0, <1.4.0-dev" }
+
+              its([:requirement]) { is_expected.to eq(">=1.2.0, <1.6.0") }
+            end
           end
 
-          context "when including a pre-release" do
-            let(:req_string) { ">=1.2.0, <1.4.0-dev" }
+          context "with `less than equal`" do
+            let(:req_string) { "> 1.0.0, <= 1.2.0" }
 
-            its([:requirement]) { is_expected.to eq(">=1.2.0, <1.6.0") }
+            its([:requirement]) { is_expected.to eq("> 1.0.0, <= 1.5.0") }
+
+            context "when already valid" do
+              let(:req_string) { "> 1.0.0, <= 1.7.0" }
+
+              its([:requirement]) { is_expected.to eq(req_string) }
+            end
+
+            context "when including a pre-release" do
+              let(:req_string) { ">=1.2.0, <=1.4.0-dev" }
+
+              its([:requirement]) { is_expected.to eq(">=1.2.0, <=1.5.0") }
+            end
           end
         end