How severe is GHSA-gm2x-2g9h-ccm8?

GHSA-gm2x-2g9h-ccm8 has a CVSS score of 2.8/10, rated LOW. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-gm2x-2g9h-ccm8?

GHSA-gm2x-2g9h-ccm8 affects the following packages: github.com/go-git/go-git/v5 (Go). Ecosystems affected: Go.

How do I fix GHSA-gm2x-2g9h-ccm8?

Update github.com/go-git/go-git/v5 to 5.17.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gm2x-2g9h-ccm8 is resolved across your whole dependency graph.

How do I detect GHSA-gm2x-2g9h-ccm8 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/go-git/go-git/v5. 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-gm2x-2g9h-ccm8 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-gm2x-2g9h-ccm8?

O3 pinpoints whether GHSA-gm2x-2g9h-ccm8 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-gm2x-2g9h-ccm8 actively exploited in the wild?

No public exploit code has been indexed for GHSA-gm2x-2g9h-ccm8 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-gm2x-2g9h-ccm8?

GHSA-gm2x-2g9h-ccm8 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 5th 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-gm2x-2g9h-ccm8 published, and has it been updated?

GHSA-gm2x-2g9h-ccm8 was published on March 30, 2026 and was last updated on April 7, 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-gm2x-2g9h-ccm8

LOW

go-git missing validation decoding Index v4 files leads to panic

Also known asCVE-2026-33762GO-2026-4909

Published

Mar 30, 2026

Updated

Apr 7, 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 Risk5th percentile+0.15%

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

🐹github.com/go-git/go-git/v5

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

Impact

go-git’s index decoder for format version 4 fails to validate the path name prefix length before applying it to the previously decoded path name. A maliciously crafted index file can trigger an out-of-bounds slice operation, resulting in a runtime panic during normal index parsing.

This issue only affects Git index format version 4. Earlier formats (go-git supports only v2 and v3) are not vulnerable to this issue.

An attacker able to supply a crafted .git/index file can cause applications using go-git to panic while reading the index. If the application does not recover from panics, this results in process termination, leading to a denial-of-service (DoS) condition.

Exploitation requires the ability to modify or inject a Git index file within the local repository in disk. This typically implies write access to the .git directory.

Patches

Users should upgrade to v5.17.1, or the latest v6 pseudo-version, in order to mitigate this vulnerability.

Credit

go-git maintainers thank @kq5y for finding and reporting this issue privately to the go-git project.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/go-git/go-git/v5`	all versions	5.17.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/go-git/go-git/v5. 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 github.com/go-git/go-git/v5 to 5.17.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gm2x-2g9h-ccm8 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-gm2x-2g9h-ccm8 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-gm2x-2g9h-ccm8. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Impact `go-git`’s index decoder for format version 4 fails to validate the path name prefix length before applying it to the previously decoded path name. A maliciously crafted index file can trigger an out-of-bounds slice operation, resulting in a runtime panic during normal index parsing. This issue only affects Git index format version 4. Earlier formats (`go-git` supports only `v2` and `v3`) are not vulnerable to this issue. An attacker able to supply a crafted `.git/index` file can cause applications using go-git to panic while reading the index. If the application does not recover

O3 Security · Impact-Aware SCA

Is GHSA-gm2x-2g9h-ccm8 in your dependencies?

O3 detects GHSA-gm2x-2g9h-ccm8 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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