Vulnerability · Published Oct 21, 2026 · Assigned by VulnCheck

CVE-2026-114097Dulwich 0.23.1 before 1.2.8 Symlink Path Traversal via filter_branch Index Filter

High 7.8

In plain English

A high-severity path traversal in dulwich from jelmer. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.8High

Exploit odds (30 days)0.2%top 91.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Dulwich from 0.23.1 before 1.2.8 contains a path traversal vulnerability in CommitFilter._apply_index_filter() that allows attackers to write files outside the working directory via symlinks persisting between commits. Attackers can craft a repository where an ancestor commit's symlink redirects a descendant commit's file writes during filter_branch, enabling code execution by writing into .git/hooks.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	dulwich	no fix listed	DEBIAN-CVE-2026-114097
Debian:13	dulwich	no fix listed	DEBIAN-CVE-2026-114097
Debian:14	dulwich	1.2.8-1	DEBIAN-CVE-2026-114097
PyPI	dulwich	1.2.8	GHSA-5fqc-mrg8-w798
Ubuntu:22.04:LTS	dulwich	no fix listed	UBUNTU-CVE-2026-114097
Ubuntu:24.04:LTS	dulwich	no fix listed	UBUNTU-CVE-2026-114097
Ubuntu:26.04:LTS	dulwich	no fix listed	UBUNTU-CVE-2026-114097

Affected products (as reported)

Vendor	Product	Versions
jelmer	dulwich	0.23.1 – before 1.2.8

Weakness: CWE-22 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

GitHub Security Advisory (GHSA-5fqc-mrg8-w798) vendor-advisory
VulnCheck Advisory: Dulwich 0.23.1 before 1.2.8 Symlink Path Traversal via filter_branch Index Filter third-party-advisory