nbdime · GitPython: Denial of Service via catastrophic backtracking (ReDoS) in Actor.name_email_regex — commit author/committer
Affects nbdimeSource GCVE Database
Not known to be exploited · CVSS 8.7 High : upgrade to 4.0.4_8 soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.0.4_8
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 9 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade nbdime to 4.0.4_8.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewnbdimepkg:brew/nbdimeOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in GitPython to address this ReDoS vulnerability. Users should upgrade to a patched version once released. Until then, avoid processing untrusted git commit objects with GitPython or apply input validation to limit author and committer field lengths. Additionally, ensure git server configurations enable receive.fsckObjects to reject malformed commits at the server side, preventing injection of malicious objects. Monitor vendor advisories for official patches and remediation guidance.
Description
GitPython contains a Regular Expression Denial of Service (ReDoS) vulnerability in the Actor.name_email_regex pattern used to parse commit author and committer headers. The regex causes catastrophic backtracking when processing a commit with a long string containing an unterminated '<' character, leading to CPU exhaustion proportional to the square of the input length. This can block GitPython API calls that access commit author or committer metadata for extended periods, impacting CI runners, code-hosting backends, and repository scanning tools that process untrusted commits.
References
- github.com/gitpython-developers/GitPython/security/advisories/GHSA-g5vv-9gxw-82hx (opens in a new tab)
- github.com/gitpython-developers/GitPython/pull/2215 (opens in a new tab)
- github.com/gitpython-developers/GitPython/commit/751473a5f3221d6f989291cbebcc404353fd3ba8 (opens in a new tab)
- github.com/gitpython-developers/GitPython (opens in a new tab)
- github.com/gitpython-developers/GitPython/releases/tag/3.1.60 (opens in a new tab)
- github.com/pypa/advisory-database/tree/main/vulns/gitpython/PYSEC-2026-3984.yaml (opens in a new tab)
- vulncheck.com/advisories/gitpython-before-3.1.60-denial-of-service-via-redos (opens in a new tab)