CVE-2023-27476
HIGHCVE-2023-27476 is a high-severity (CVSS 8.2) XML External Entity (XXE) vulnerability in owslib. O3 Security confirms whether CVE-2023-27476 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
XML External Entity (XXE) Injection in OWSLib
Blast Radius
owslibReal-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
OWSLib is a Python package for client programming with Open Geospatial Consortium (OGC) web service interface standards, and their related content models. OWSLib's XML parser (which supports both lxml and xml.etree) does not disable entity resolution, and could lead to arbitrary file reads from an attacker-controlled XML payload. This affects all XML parsing in the codebase. This issue has been addressed in version 0.28.1. All users are advised to upgrade. The only known workaround is to patch the library manually. See GHSA-8h9c-r582-mggc for details.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | owslib | all versions | 0.28.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for owslib. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update owslib to 0.28.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-27476 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 pinpoints whether CVE-2023-27476 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2023-27476. 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-2023-27476 in your dependencies?
O3 detects CVE-2023-27476 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.