CVE-2008-2942 — mercurial
CVE-2008-2942 is a Path Traversal vulnerability in mercurial. 1 public exploit reference exists, so weaponization risk is real. A fix is available for mercurial — see the affected versions and patch details below.
Mercurial Directory traversal vulnerability
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
mercurialReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Directory traversal vulnerability in patch.py in Mercurial 1.0.1 allows user-assisted attackers to modify arbitrary files via ".." (dot dot) sequences in a patch file.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | mercurial | all versions | 1.0.2pip install --upgrade 'mercurial==1.0.2' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mercurial, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update mercurial to 1.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2008-2942 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2008-2942 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2008-2942. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2008-2942 in your dependencies?
O3 Security finds CVE-2008-2942 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.