diff --git a/.github/workflows/continuous-integration.yml b/.github/workflows/continuous-integration.yml
index 2473f17ba3..3043a6821a 100644
--- a/.github/workflows/continuous-integration.yml
+++ b/.github/workflows/continuous-integration.yml
@@ -21,16 +21,16 @@ jobs:
             epVersion: 2.10.0
           - os: macos-latest
             java: 11
-            epVersion: 2.26.1
+            epVersion: 2.27.1
           - os: ubuntu-latest
             java: 11
-            epVersion: 2.26.1
+            epVersion: 2.27.1
           - os: windows-latest
             java: 11
-            epVersion: 2.26.1
+            epVersion: 2.27.1
           - os: ubuntu-latest
             java: 17
-            epVersion: 2.26.1
+            epVersion: 2.27.1
       fail-fast: false
     runs-on: ${{ matrix.os }}
     steps:
@@ -63,7 +63,7 @@ jobs:
         with:
           arguments: codeCoverageReport
         continue-on-error: true
-        if: runner.os == 'Linux' && matrix.java == '11' && matrix.epVersion == '2.26.1' && github.repository == 'uber/NullAway'
+        if: runner.os == 'Linux' && matrix.java == '11' && matrix.epVersion == '2.27.1' && github.repository == 'uber/NullAway'
       - name: Upload coverage reports to Codecov
         uses: codecov/codecov-action@v4
         with:
diff --git a/gradle/dependencies.gradle b/gradle/dependencies.gradle
index 596096adc8..54a5e3ef8f 100755
--- a/gradle/dependencies.gradle
+++ b/gradle/dependencies.gradle
@@ -19,7 +19,7 @@ import org.gradle.util.VersionNumber
 // The oldest version of Error Prone that we support running on
 def oldestErrorProneVersion = "2.10.0"
 // Latest released Error Prone version that we've tested with
-def latestErrorProneVersion = "2.26.1"
+def latestErrorProneVersion = "2.27.1"
 // Default to using latest tested Error Prone version
 def defaultErrorProneVersion =  latestErrorProneVersion
 def errorProneVersionToCompileAgainst = defaultErrorProneVersion
diff --git a/nullaway/src/main/java/com/uber/nullaway/dataflow/cfg/NullAwayCFGBuilder.java b/nullaway/src/main/java/com/uber/nullaway/dataflow/cfg/NullAwayCFGBuilder.java
index 768eb0a4ea..c848d4665c 100644
--- a/nullaway/src/main/java/com/uber/nullaway/dataflow/cfg/NullAwayCFGBuilder.java
+++ b/nullaway/src/main/java/com/uber/nullaway/dataflow/cfg/NullAwayCFGBuilder.java
@@ -223,7 +223,7 @@ public <R, D> R accept(TreeVisitor<R, D> visitor, D data) {
 
     @Override
     public MethodInvocationNode visitMethodInvocation(MethodInvocationTree tree, Void p) {
-      MethodInvocationNode originalNode = super.visitMethodInvocation(tree, p);
+      MethodInvocationNode originalNode = super.visitMethodInvocation(tree, null);
       return handler.onCFGBuildPhase1AfterVisitMethodInvocation(this, tree, originalNode);
     }
   }
diff --git a/nullaway/src/main/java/com/uber/nullaway/handlers/contract/ContractCheckHandler.java b/nullaway/src/main/java/com/uber/nullaway/handlers/contract/ContractCheckHandler.java
index bfbadf7177..d0386909d6 100644
--- a/nullaway/src/main/java/com/uber/nullaway/handlers/contract/ContractCheckHandler.java
+++ b/nullaway/src/main/java/com/uber/nullaway/handlers/contract/ContractCheckHandler.java
@@ -156,7 +156,7 @@ public Void visitReturn(ReturnTree returnTree, Void unused) {
                         returnState,
                         null));
           }
-          return super.visitReturn(returnTree, unused);
+          return super.visitReturn(returnTree, null);
         }
       }.scan(state.getPath(), null);
     }