Vulnerability · Published Apr 15, 2026 · Assigned by GitHub_M
CVE-2026-40256Weblate: Prefix-Based Repository Boundary Check Bypass via Symlink/Junction Path Prefix Collision
Medium 5.0
In plain English
A medium-severity path traversal in weblate from WeblateOrg. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Weblate is a web based localization tool. In versions prior to 5.17, repository-boundary validation relies on string prefix checks on resolved absolute paths. In multiple code paths, the check uses startswith against the repository root path. This is not path-segment aware and can be bypassed when the external path shares the same string prefix as the repository path (for example, repo and repo_outside). This issue has been fixed in version 5.17.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | weblate | 5.17 | GHSA-ffgh-3jrf-8wvh |
| PyPI | weblate | 5.17 | PYSEC-2026-2315 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| WeblateOrg | weblate | < 5.17 |
Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N