gix-packetline: reachable panic on empty side-band packet (pre-auth network DoS)

Exploitation

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

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-82250: 0.43% estimated exploitation activity in the next 30 days; percentile 37.59 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary gix-packetline panics when it receives a side-band packet line that contains only the band-id byte with an empty payload. A malicious Git server - or any remote a victim clones/fetches from - can abort the gix client process during a normal fetch. This is a pre-authentication, network-triggered denial of service. Details In gix-packetline/src/lib.rs, impl From<&[u8] for TextRef strips a trailing newline with d[d.len() - 1]: https://github.com/GitoxideLabs/gitoxide/blob/eac50e1207e2549b23302c9faf595a420b9919fc/gix-packetline/src/lib.rs#L199 When d is empty (an empty side-band payload after the band-id byte is removed), d.len() - 1 underflows usize (to 18446744073709551615, i.e. 0 - 1) and the index access panics. The empty side-band line is attacker-supplied and is reached during a normal fetch. (Related: an unchecked splitatmut in gix-packetline/src/blockingio/read.rs is in the same DoS class and worth hardening in the same pass.) PoC Confirmed against gix v0.54.0 (crate…

Published by the source

28 Aug 2026, 16:09 UTC

Last modified by the source

10 Sep 2026, 03:51 UTC

Source last checked

26 Oct 2026, 15:43 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-2vh6-hw4j-32ww

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-2vh6-hw4j-32ww

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# Patch Next advisory brief: CVE-2026-82250

Advisory: gix-packetline: reachable panic on empty side-band packet (pre-auth network DoS)
IDs: CVE-2026-82250, GHSA-2vh6-hw4j-32ww
Record: https://patchnext.com/advisories/cve-2026-82250 (revision 2, source checked 26 Oct 2026, 15:43 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: gix-packetline 0.21.5. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io gix-packetline: affected <= 0.21.4; fixed in 0.21.5

## Suggested inspection (read-only)
- crates.io gix-packetline: 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-packetline.
- 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://osv.dev/vulnerability/GHSA-2vh6-hw4j-32ww (OSV record GHSA-2vh6-hw4j-32ww lists affected ranges: crates.io gix-packetline >=0 <0.21.5 (fixed))
- Verified: https://github.com/advisories/GHSA-2vh6-hw4j-32ww (GitHub-reviewed advisory GHSA-2vh6-hw4j-32ww lists affected ranges: crates.io gix-packetline >=0 <=0.21.4)

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