CVE-2013-2037 is a high-severity (CVSS 7.5) Improper Input Validation vulnerability in httplib2. 2 public exploit references exist, so weaponization risk is real. A fix is available for httplib2 — see the affected versions and patch details below.
httplib2 incorrectly checks SSL certificate
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2013-2037 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 384,189 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
httplib2Real-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
httplib2 0.7.2, 0.8, and earlier, after an initial connection is made, does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | httplib2 | all versions | 0.10.1pip install --upgrade 'httplib2==0.10.1' |
Affected Products
ubuntu linuxcanonicalhttplib2httplib2_projectResearch 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 httplib2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update httplib2 to 0.10.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2013-2037 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.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Frequently Asked Questions
Is CVE-2013-2037 in your dependencies?
Find it across PyPI, including transitive dependencies.