Security incident · CVE-2026-114097
Dulwich: Symlink directory traversal in filter-branch index_filter via cross-commit state persistence
Published Oct 2, 2026 · catalog updated Oct 21, 2026 · Dulwich: Symlink directory traversal
Last checked Oct 25, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2026-114097. EPSS is 0.19%. Act only if a listed version of Dulwich: Symlink directory traversal is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (Dulwich: Symlink directory traversal).
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High8.6
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.19%
- Remediation
- Advisory link
- Affected products
- PyPI dulwich
## Summary Dulwich's is vulnerable to symlink directory traversal. When processing commit history, materialized tree entries (including symlinks) persist in the working directory between commits, allowing a symlink from an ancestor commit to redirect file writes from a descendant commit to arbitrary filesystem locations. ## Root Cause at calls which materializes all tree entries to the current working directory. The block (line 229-230) only cleans up the temporary index file ( ) — NOT the filesystem files written to CWD. When processes parents recursively first (line 260), files materialized from ancestor commits persist and affect processing of descendant commits. On dulwich 1.2.7, has no symlink protection, and only validates name patterns, not filesystem state. ## Impact An attacker can craft a malicious repository where running with an index filter writes attacker-controlled content to arbitrary filesystem locations via symlink traversal. This achieves RCE if the write targets . ## Attack Scenario 1. Attacker creates a repository where commit history (linearized) has: - Ancestor commit: tree entry (mode 120000, symlink → ) - Descendant commit: tree entry (mode 100644, attacker content) 2. Victim clones repository and runs with an index filter 3. processes ancestor first → materializes as symlink to in CWD 4. CWD is NOT cleaned between commits 5. Processing descendant: → True (symlink exists). → follows intermediate symlink → writes to ## Suggested Fix Clean the CWD between commit iterations in , or verify that no intermediate path components are symlinks before writing files. Reported by **zx (Jace)**
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- PyPI dulwich0.23.1 → 1.2.8
How to fix CVE-2026-114097
Upgrade
CVE-2026-114097 lists a fix boundary at 1.2.8. Compare the installed build with that boundary before you change production.
Version check
Seen in 0.23.1 → 1.2.8
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-114097. EPSS is 0.19%. Act only if a listed version of Dulwich: Symlink directory traversal is installed.
Which versions are affected?
Compare what you have installed with 0.23.1 → 1.2.8. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-22: Path Traversal; CWE-59: Link Following. EPSS 0.19%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Oct 2, 2026 · GitHub Advisory Database
Detected
## Summary Dulwich's is vulnerable to symlink directory traversal. When processing commit history, materialized tree entries (including symlinks) persist in the working directory between commits, allowing a symlink from an ancestor commit to redirect file writes from a descendant commit to arbitrary filesystem locations. ## Root Cause at calls which materializes all tree entries to the current wor
Oct 21, 2026 · GitHub Advisory Database
Fix available
dulwich fixed in 1.2.8
Oct 21, 2026 · GitHub Advisory Database
Fix available
dulwich fixed in 1.2.8
Oct 21, 2026 · GitHub Advisory Database
Updated
## Summary Dulwich's is vulnerable to symlink directory traversal. When processing commit history, materialized tree entries (including symlinks) persist in the working directory between commits, allowing a symlink from an ancestor commit to redirect file writes from a descendant commit to arbitrary filesystem locations. ## Root Cause at calls which materializes all tree entries to the current wor
Sources
- CVE.orgVulnerability recordCVE-2026-114097
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-114097
30-day exploitation probability 0.19%
first.org - GitHub Advisory DatabasePackage advisoryGHSA-5fqc-mrg8-w798
GitHub Advisory Database record mirrored by OSV.
github.com - OpenSSF OSV / OSV ScannerPackage advisoryGHSA-5fqc-mrg8-w798
Dulwich: Symlink directory traversal in filter-branch index_filter via cross-commit state persistence
osv.dev - PyPA Advisory DatabasePackage advisoryGHSA-5fqc-mrg8-w798
Dulwich: Symlink directory traversal in filter-branch index_filter via cross-commit state persistence
osv.dev
References
Freshness
Last verified in this catalog Oct 25, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- FIRST EPSSOct 25, 2026
- CVE.orgOct 21, 2026
- PyPA Advisory DatabaseOct 21, 2026
- GitHub Advisory DatabaseOct 21, 2026
- OpenSSF OSV / OSV ScannerOct 21, 2026