CVE-2026-34165: go-git: Maliciously crafted idx file can cause asymmetric memory consumption

Severity: medium (CVSS 5.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-31 · updated 2026-07-24
Weakness: CWE-191

Description

go-git is an extensible git implementation library written in pure Go. From version 5.0.0 to before version 5.17.1, a vulnerability has been identified in which a maliciously crafted .idx file can cause asymmetric memory consumption, potentially exhausting available memory and resulting in a denial-of-service (DoS) condition. Exploitation requires write access to the local repository's .git directory, it order to create or alter existing .idx files. This issue has been patched in version 5.17.1.

Affected products

go-git: from 5.0.0 before 5.17.1 — fixed in 5.17.1

How to fix

Upgrade to a fixed version: go-git 5.17.1. Check the vendor advisory for mitigations.

References

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