GitPython before 3.1.60 fails to properly validate the git directory location, allowing attackers to impersonate the git directory using tracked files like gitdir, commondir, and HEAD. Attackers can execute arbitrary code by placing a malicious pre-commit hook in the tracked hooks directory that executes when a victim calls index.commit() on a cloned or opened repository.
CVE-2026-87817
HIGHPre-NVD 8.88.8—
EchelonGraph scoreHIGH confidence
Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-09. a secondary CVSS source baseline 8.8; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.8Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.8
- EG Score
- 8.8(high)
- EG Risk
- 55(Track)EG Risk 55/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity88% × 45%Exploitation0% × 40%Automatability100% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 26%
- KEV
- Not listed
Published
September 9, 2026
Last Modified
September 16, 2026
Advisory Details (2)
Auto-updated Sep 9, 2026🔬 Proof of concept available. Patch available. Sources: github.
generic
GitPython before 3.1.60 Remote Code Execution via Git Directory Impersonation | Advisories | VulnCheck
https://www.vulncheck.com/advisories/gitpython-before-3.1.60-remote-code-execution-via-git-directory-impersonationgithub Patch Available🟡 PoC Available
Repository content can impersonate the git directory, leading to arbitrary code execution · Advisory · gitpython-developers/GitPython · GitHub
https://github.com/gitpython-developers/GitPython/security/advisories/GHSA-239g-whfq-7xj9Vendor Advisories for CVE-2026-87817(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Frequently asked(5)
What is CVE-2026-87817?
CVE-2026-87817 is a high vulnerability published on September 9, 2026. GitPython before 3.1.60 fails to properly validate the git directory location, allowing attackers to impersonate the git directory using tracked files like gitdir, commondir, and HEAD. Attackers can execute arbitrary code by placing a malicious pre-commit hook in the tracked hooks directory that…
When was CVE-2026-87817 disclosed?
CVE-2026-87817 was first published in the National Vulnerability Database on September 9, 2026, with the most recent update on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-87817 actively exploited?
CVE-2026-87817 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 74.0% of all scored CVEs.
What is the CVSS score of CVE-2026-87817?
CVE-2026-87817 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2026-87817?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-87817, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
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