CVSS 4.0
6.3 mediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NCVE-2026-21860
Medium (6.3) in palletsprojects werkzeug. EPSS 0.5% chance of exploitation in the next 30 days. Fixed in werkzeug 3.1.5.
Werkzeug is a comprehensive WSGI web application library. Prior to version 3.1.5, Werkzeug's safe_join function allows path segments with Windows device names that have file extensions or trailing spaces. On Windows, there are special device names such as CON, AUX, etc that are implicitly present and readable in every directory. Windows still accepts them with any file extension, such as CON.txt, or trailing spaces such as CON. This issue has been patched in version 3.1.5.
Severity
CVSS 3.1
5.3 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 41% of CVEs (scores of 2026-10-31)
- CWE
- CWE-67
- Published
- Modified
- Record from
- the NVD, synced
Affected
- palletsprojects:werkzeug
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-87hc-h4r5-73f7 | PyPI | werkzeug | <3.1.5 | 3.1.5 |
| PYSEC-2026-2044 | PyPI | werkzeug | <3.1.5 | 3.1.5 |