CVE-2026-122299
HIGH
MEDIUM
Priority: 0.03
BB Relevance:
67/100
Published: 2026-11-04
Modified: 2026-11-09
First seen: 2026-11-04
Status: active
Attack Surface
Network
Low Complexity
No Auth
Conf. Impact
Integ. Impact
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
Active
AT:
None
VC:
High
VI:
High
VA:
High
Description
Dulwich before 1.2.20 contains a commit object parsing vulnerability where the read path in _parse_commit resolves a duplicate tree header to the last occurrence instead of the first, diverging from core git's resolution behavior, while Poetry 2.5.1 ships this version and uses dulwich by default for git dependency installation. Attackers can craft a commit object with two tree headers so that reviewers and CI using git see a benign tree while Poetry's dulwich-based checkout resolves to a different attacker-controlled tree containing malicious build scripts such as setup.py, resulting in unreviewed code execution on the install or build host.