GHSA-4mgv-m5cm-f9h7 is a high-severity (CVSS 7.5) CWE-532 vulnerability in hashicorp/vault-action. 1 public exploit reference exists, so weaponization risk is real. A fix is available for hashicorp/vault-action — see the affected versions and patch details below.
Vault GitHub Action did not correctly mask multi-line secrets in output
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-4mgv-m5cm-f9h7 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 376,715 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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 |
Research 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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-4mgv-m5cm-f9h7 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-4mgv-m5cm-f9h7. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-4mgv-m5cm-f9h7 in your dependencies?
O3 Security finds GHSA-4mgv-m5cm-f9h7 across GitHub Actions dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.