Vault GitHub Action did not correctly mask multi-line secrets in outputGHSA-4mgv-m5cm-f9h7
HIGHFix: hashicorp/vault-action#208GHSA-4mgv-m5cm-f9h7 is a high-severity (CVSS 7.5) CWE-532 vulnerability in hashicorp/vault-action. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for hashicorp/vault-action — see the affected versions and patch details below.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
hashicorp/vault-actionReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects GitHub Actions packages — download data is not available via public APIs for these ecosystems.
Description
HashiCorp vault-action (aka Vault GitHub Action) before 2.2.0 allows attackers to obtain sensitive information from log files because a multi-line secret was not correctly registered with GitHub Actions for log masking.
The vault-action implementation did not correctly handle the marking of multi-line variables. As a result, multi-line secrets were not correctly masked in vault-action output.
Remediation: Customers using vault-action should evaluate the risk associated with this issue, and consider upgrading to vault-action 2.2.0 or newer. Please refer to https://github.com/marketplace/actions/hashicorp-vault for more information.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦GitHub Actions | hashicorp/vault-action | all versions | 2.2.0 |
Affected Products
vault-actionhashicorpResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for hashicorp/vault-action, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update hashicorp/vault-action to 2.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4mgv-m5cm-f9h7 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is GHSA-4mgv-m5cm-f9h7 in your dependencies?
Find it across GitHub Actions, including transitive dependencies.