CVE-2026-55227 is a medium-severity (CVSS 4.3) CWE-203 vulnerability in weblate. A fix is available for weblate — see the affected versions and patch details below.
Observable object existence disclosure in private Weblate projects via globally scoped object lookups
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-55227.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-55227 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
weblateReal-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
Weblate is a web-based localization tool. In versions prior to 2026.7, several endpoints look up objects in a globally scoped manner rather than restricting the lookup to projects the user can access, so they return HTTP 403 (Forbidden) instead of 404 (Not Found) when a user requests an object they are not authorized to see. This difference lets unauthorized users infer whether a given object exists in a private Weblate project. The issue has been fixed in version 2026.7.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | weblate | all versions | 2026.7pip install --upgrade 'weblate==2026.7' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for weblate, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update weblate to 2026.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55227 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.
Frequently Asked Questions
Is CVE-2026-55227 in your dependencies?
Find it across PyPI, including transitive dependencies.