{"id":"DEBIAN-CVE-2026-42563","details":"Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.24.0 and prior to version 1.2.5, Dulwich's `ProcessMergeDriver` substitutes the file path (from the git tree, controllable by an attacker via a malicious branch) into the merge driver command via the `%P` placeholder and executes it with `subprocess.run(..., shell=True)`. An attacker who can cause a victim to merge an untrusted branch can achieve arbitrary command execution by crafting malicious file paths. Version 1.2.5 fixes the issue.","modified":"2026-09-01T16:06:42.640126652Z","published":"2026-06-10T23:16:46.413Z","upstream":["CVE-2026-42563"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-42563"}],"affected":[{"package":{"name":"dulwich","ecosystem":"Debian:12","purl":"pkg:deb/debian/dulwich?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.21.2-1","0.21.5-1","0.21.6-1","0.22.5-1","0.22.7-1","0.22.7-2","0.24.10-1","0.24.2-1","0.24.2-2","1.0.0-1","1.0.0-2","1.1.0-1","1.1.0-2","1.1.0-3","1.2.0-1","1.2.1-1","1.2.11-1","1.2.12-1","1.2.5-1","1.2.7-1","1.2.7-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42563.json"}},{"package":{"name":"dulwich","ecosystem":"Debian:13","purl":"pkg:deb/debian/dulwich?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.22.7-1","0.22.7-2","0.24.10-1","0.24.2-1","0.24.2-2","1.0.0-1","1.0.0-2","1.1.0-1","1.1.0-2","1.1.0-3","1.2.0-1","1.2.1-1","1.2.11-1","1.2.12-1","1.2.5-1","1.2.7-1","1.2.7-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42563.json"}},{"package":{"name":"dulwich","ecosystem":"Debian:14","purl":"pkg:deb/debian/dulwich?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.5-1"}]}],"versions":["0.22.7-1","0.22.7-2","0.24.10-1","0.24.2-1","0.24.2-2","1.0.0-1","1.0.0-2","1.1.0-1","1.1.0-2","1.1.0-3","1.2.0-1","1.2.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42563.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}