Merge pull request #22235 from JarLob/fix/actions-envvar-injection-precision

Actions: Fix FP in envvar injection

Author: aschackmull

actions/ql/lib/codeql/actions/security/EnvVarInjectionQuery.qll

@@ -151,7 +151,7 @@ Event getRelevantNonArtifactEventInPrivilegedContext(DataFlow::Node sink) {
 private module EnvVarInjectionConfig implements DataFlow::ConfigSig {
   predicate isSource(DataFlow::Node source) {
     source instanceof RemoteFlowSource and
-    not source.(RemoteFlowSource).getSourceType() = ["branch", "username"]
+    not source.(RemoteFlowSource).getSourceType() = ["branch", "label", "username"]
   }
 
   predicate isSink(DataFlow::Node sink) { sink instanceof EnvVarInjectionSink }

actions/ql/src/Security/CWE-077/EnvVarInjectionCritical.ql

@@ -19,9 +19,16 @@ import codeql.actions.dataflow.FlowSources
 import EnvVarInjectionFlow::PathGraph
 import codeql.actions.security.ControlChecks
 
+bindingset[source, event]
+pragma[inline_late]
+private predicate hasSameEventName(RemoteFlowSource source, Event event) {
+  source.getEventName() = event.getName()
+}
+
 from EnvVarInjectionFlow::PathNode source, EnvVarInjectionFlow::PathNode sink, Event event
 where
   EnvVarInjectionFlow::flowPath(source, sink) and
+  hasSameEventName(source.getNode(), event) and
   // exclude paths to file read sinks from non-artifact sources
   (
     // source is text

actions/ql/src/change-notes/2026-07-18-envvar-injection-precision.md

@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* The `actions/envvar-injection/critical` query now requires the untrusted source and privileged context to originate from the same trigger event. The environment variable injection queries also no longer treat pull request head labels as injection-capable because they cannot contain newlines.

actions/ql/test/query-tests/Security/CWE-077/.github/workflows/test18.yml

@@ -8,6 +8,8 @@ on:
 
 jobs:
   tests:
+    permissions:
+      contents: write
     runs-on: ubuntu-latest
     steps:
       - name: Checkout Repository
@@ -30,3 +32,7 @@ jobs:
           # Delete non-alphanumeric characters and limit to 75 chars which is the branch title limit in GitHub
           SAFE_PULL_REQUEST_TITLE=$(echo "${GITHUB_EVENT_PULL_REQUEST_TITLE}" | tr -cd '[:alnum:]_ -' | cut -c1-75)
           echo "SAFE_PULL_REQUEST_TITLE=$SAFE_PULL_REQUEST_TITLE" >> $GITHUB_ENV
+      - name: Keep source and privilege events correlated
+        env:
+          BODY: ${{ github.event.pull_request.body }}
+        run: echo "BODY=$BODY" >> $GITHUB_ENV

actions/ql/test/query-tests/Security/CWE-077/.github/workflows/test4.yml

@@ -66,6 +66,10 @@ jobs:
           ${TITLE}
           EOL
           echo REPO_NAME=$(cat issue.txt | sed 's/\r/\n/g' | grep -ioE '\s*[a-z0-9_-]+/[a-z0-9_-]+\s*$' | tr -d ' ') >> $GITHUB_ENV
+      - env:
+          LABEL: ${{ github.event.pull_request.head.label }}
+        run: |
+          echo "PR_LABEL=$LABEL" >> $GITHUB_ENV
 
 
 

actions/ql/test/query-tests/Security/CWE-077/EnvVarInjectionCritical.expected

@@ -29,6 +29,7 @@ edges
 | .github/workflows/test12.yml:55:9:61:6 | Uses Step | .github/workflows/test12.yml:63:14:68:29 | {\n  echo 'PRERELEASE_REPORT<<EOF'\n  cat prerelease-report.md\n  echo EOF\n} >> "$GITHUB_ENV"\n | provenance | Config |
 | .github/workflows/test16.yml:10:9:15:6 | Uses Step | .github/workflows/test16.yml:15:14:17:63 | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt)" >> $GITHUB_ENV\n | provenance | Config |
 | .github/workflows/test16.yml:10:9:15:6 | Uses Step | .github/workflows/test16.yml:18:14:20:77 | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt \| tr ',' '\\n')" >> $GITHUB_ENV\n | provenance | Config |
+| .github/workflows/test18.yml:37:18:37:54 | github.event.pull_request.body | .github/workflows/test18.yml:38:14:38:45 | echo "BODY=$BODY" >> $GITHUB_ENV | provenance | Config |
 nodes
 | .github/workflows/artifactpoisoning51.yml:13:9:15:6 | Run Step | semmle.label | Run Step |
 | .github/workflows/artifactpoisoning51.yml:19:14:20:57 | echo "pr_number=$(cat foo/bar)" >> $GITHUB_ENV\n | semmle.label | echo "pr_number=$(cat foo/bar)" >> $GITHUB_ENV\n |
@@ -91,6 +92,8 @@ nodes
 | .github/workflows/test16.yml:10:9:15:6 | Uses Step | semmle.label | Uses Step |
 | .github/workflows/test16.yml:15:14:17:63 | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt)" >> $GITHUB_ENV\n | semmle.label | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt)" >> $GITHUB_ENV\n |
 | .github/workflows/test16.yml:18:14:20:77 | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt \| tr ',' '\\n')" >> $GITHUB_ENV\n | semmle.label | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt \| tr ',' '\\n')" >> $GITHUB_ENV\n |
+| .github/workflows/test18.yml:37:18:37:54 | github.event.pull_request.body | semmle.label | github.event.pull_request.body |
+| .github/workflows/test18.yml:38:14:38:45 | echo "BODY=$BODY" >> $GITHUB_ENV | semmle.label | echo "BODY=$BODY" >> $GITHUB_ENV |
 subpaths
 #select
 | .github/workflows/artifactpoisoning51.yml:19:14:20:57 | echo "pr_number=$(cat foo/bar)" >> $GITHUB_ENV\n | .github/workflows/artifactpoisoning51.yml:13:9:15:6 | Run Step | .github/workflows/artifactpoisoning51.yml:19:14:20:57 | echo "pr_number=$(cat foo/bar)" >> $GITHUB_ENV\n | Potential environment variable injection in $@, which may be controlled by an external user ($@). | .github/workflows/artifactpoisoning51.yml:19:14:20:57 | echo "pr_number=$(cat foo/bar)" >> $GITHUB_ENV\n | echo "pr_number=$(cat foo/bar)" >> $GITHUB_ENV\n | .github/workflows/artifactpoisoning51.yml:4:3:4:14 | workflow_run | workflow_run |

actions/ql/test/query-tests/Security/CWE-077/EnvVarInjectionMedium.expected

@@ -29,6 +29,7 @@ edges
 | .github/workflows/test12.yml:55:9:61:6 | Uses Step | .github/workflows/test12.yml:63:14:68:29 | {\n  echo 'PRERELEASE_REPORT<<EOF'\n  cat prerelease-report.md\n  echo EOF\n} >> "$GITHUB_ENV"\n | provenance | Config |
 | .github/workflows/test16.yml:10:9:15:6 | Uses Step | .github/workflows/test16.yml:15:14:17:63 | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt)" >> $GITHUB_ENV\n | provenance | Config |
 | .github/workflows/test16.yml:10:9:15:6 | Uses Step | .github/workflows/test16.yml:18:14:20:77 | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt \| tr ',' '\\n')" >> $GITHUB_ENV\n | provenance | Config |
+| .github/workflows/test18.yml:37:18:37:54 | github.event.pull_request.body | .github/workflows/test18.yml:38:14:38:45 | echo "BODY=$BODY" >> $GITHUB_ENV | provenance | Config |
 nodes
 | .github/workflows/artifactpoisoning51.yml:13:9:15:6 | Run Step | semmle.label | Run Step |
 | .github/workflows/artifactpoisoning51.yml:19:14:20:57 | echo "pr_number=$(cat foo/bar)" >> $GITHUB_ENV\n | semmle.label | echo "pr_number=$(cat foo/bar)" >> $GITHUB_ENV\n |
@@ -91,5 +92,7 @@ nodes
 | .github/workflows/test16.yml:10:9:15:6 | Uses Step | semmle.label | Uses Step |
 | .github/workflows/test16.yml:15:14:17:63 | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt)" >> $GITHUB_ENV\n | semmle.label | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt)" >> $GITHUB_ENV\n |
 | .github/workflows/test16.yml:18:14:20:77 | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt \| tr ',' '\\n')" >> $GITHUB_ENV\n | semmle.label | # VULNERABLE\necho "PR_NUMBER=$(cat pr_number.txt \| tr ',' '\\n')" >> $GITHUB_ENV\n |
+| .github/workflows/test18.yml:37:18:37:54 | github.event.pull_request.body | semmle.label | github.event.pull_request.body |
+| .github/workflows/test18.yml:38:14:38:45 | echo "BODY=$BODY" >> $GITHUB_ENV | semmle.label | echo "BODY=$BODY" >> $GITHUB_ENV |
 subpaths
 #select