How severe is GHSA-2w4f-9fgg-q2v9?

GHSA-2w4f-9fgg-q2v9 has a CVSS score of 5.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-2w4f-9fgg-q2v9?

GHSA-2w4f-9fgg-q2v9 affects the following packages: chainguard.dev/melange (Go). Ecosystems affected: Go.

How do I fix GHSA-2w4f-9fgg-q2v9?

Update chainguard.dev/melange to 0.40.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2w4f-9fgg-q2v9 is resolved across your whole dependency graph.

How do I detect GHSA-2w4f-9fgg-q2v9 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for chainguard.dev/melange. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-2w4f-9fgg-q2v9 if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-2w4f-9fgg-q2v9?

O3 pinpoints whether GHSA-2w4f-9fgg-q2v9 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-2w4f-9fgg-q2v9 actively exploited in the wild?

No public exploit code has been indexed for GHSA-2w4f-9fgg-q2v9 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-2w4f-9fgg-q2v9?

GHSA-2w4f-9fgg-q2v9 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 6th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

When was GHSA-2w4f-9fgg-q2v9 published, and has it been updated?

GHSA-2w4f-9fgg-q2v9 was published on February 4, 2026 and was last updated on February 5, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

GHSA-2w4f-9fgg-q2v9

MEDIUM

melange has a path traversal in license-path which allows reading files outside workspace

Also known asCVE-2026-25145GO-2026-4409

Published

Feb 4, 2026

Updated

Feb 5, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk6th percentile+0.16%

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.

Blast Radius

1 pkg affected

🐹chainguard.dev/melange

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

An attacker who can influence a melange configuration file (e.g., through pull request-driven CI or build-as-a-service scenarios) could read arbitrary files from the host system. The LicensingInfos function in pkg/config/config.go reads license files specified in copyright[].license-path without validating that paths remain within the workspace directory, allowing path traversal via ../ sequences. The contents of the traversed file are embedded into the generated SBOM as license text, enabling exfiltration of sensitive data through build artifacts.

Fix: Merged in commit 2f95c9f4

Acknowledgements

melange thanks Oleh Konko (@1seal) from 1seal for discovering and reporting this issue.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`chainguard.dev/melange`	≥ 0.14.0&&< 0.40.3	0.40.3

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for chainguard.dev/melange. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update chainguard.dev/melange to 0.40.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2w4f-9fgg-q2v9 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 pinpoints whether GHSA-2w4f-9fgg-q2v9 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-2w4f-9fgg-q2v9. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

An attacker who can influence a melange configuration file (e.g., through pull request-driven CI or build-as-a-service scenarios) could read arbitrary files from the host system. The `LicensingInfos` function in `pkg/config/config.go` reads license files specified in `copyright[].license-path` without validating that paths remain within the workspace directory, allowing path traversal via `../` sequences. The contents of the traversed file are embedded into the generated SBOM as license text, enabling exfiltration of sensitive data through build artifacts.

O3 Security · Impact-Aware SCA

Is GHSA-2w4f-9fgg-q2v9 in your dependencies?

O3 detects GHSA-2w4f-9fgg-q2v9 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works