CVE-2026-109351 Gitoxide gix-pack before 0.75.0 Denial of Service via Pack Header Object Count
Remote attackers can cause denial of service in Gitoxide gix-pack by sending malicious pack headers that trigger excessive memory allocation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-109351?
CVE-2026-109351 is a high-severity denial of service vulnerability in GitoxideLabs gix-pack, published on 12 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Gitoxide gix-pack before 0.75.0 contains an uncontrolled memory allocation vulnerability that allows remote attackers to abort the process by supplying a huge pack-header object count. Malicious remotes can serve a 12-byte pack header claiming 0xFFFFFFFF objects, forcing Tree::with_capacity to reserve hundreds of gigabytes and crash clone or fetch operations.
Weakness: CWE-770
Which versions are affected by CVE-2026-109351?
How do I fix CVE-2026-109351?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-109351 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109351 exists.
Sources
Also known as DEBIAN-CVE-2026-109351, GHSA-hf39-hrp5-hx3v, GHSA-x862-c2wj-4mwr, UBUNTU-CVE-2026-109351.