gix-pack has multiple DoS vectors: unchecked indexing panics and uncapped OOM allocations from crafted pack data

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N · score source

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Summary Multiple denial-of-service vectors in gix-pack: unchecked array indexing causes panics on crafted delta data, and uncapped attacker-controlled size headers enable OOM process kills. Both are triggered by malicious pack data received during clone/fetch. Details Bug 1: Unchecked array indexing in delta application (CWE-248) The apply() function in gix-pack/src/data/delta.rs (lines 33-87) reads delta instructions using unchecked data[i] indexing at 7 locations (lines 41, 45, 49, 53, 57, 61, 65). The command byte's bits indicate how many additional bytes follow, but if the delta data is truncated, the index panics: Lines 83-84 use asserteq! (not debugasserteq!) that panics in both debug and release builds: A second location in parseheaderinfo() (gix-pack/src/data/entry/decode.rs:116-129) also panics on truncated input via unchecked data[0] and data[i]. Note: PR #2059 (merged 2025-06-25) fixed the explicit panic!() for command code 0. The unchecked array indexing is a distinct…

Published by the source

5 May 2026, 19:24 UTC

Last modified by the source

5 May 2026, 19:24 UTC

Source last checked

26 Oct 2026, 15:42 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-x494-mj8g-cj27

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# Patch Next advisory brief: GHSA-x494-mj8g-cj27

Advisory: gix-pack has multiple DoS vectors: unchecked indexing panics and uncapped OOM allocations from crafted pack data
IDs: GHSA-x494-mj8g-cj27
Record: https://patchnext.com/advisories/ghsa-x494-mj8g-cj27 (revision 1, source checked 26 Oct 2026, 15:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: gix-pack 0.69.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io gix-pack: affected <= 0.68.0; fixed in 0.69.0

## Suggested inspection (read-only)
- crates.io gix-pack: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on gix-pack.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-x494-mj8g-cj27 (GitHub-reviewed advisory GHSA-x494-mj8g-cj27 lists affected ranges: crates.io gix-pack >=0 <=0.68.0)

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