MEDIUM 5.3 Microsoft
CVE-2026-21860
Werkzeug safe_join() allows Windows special device names with compound extensions
Microsoft Security Update 2026-Jan: Werkzeug safe_join() allows Windows special device names with compound extensions
Affected Products
- cbl2 python-tensorboard 2.11.0-3 on CBL Mariner 2.0
- cbl2 python-werkzeug 2.3.7-3 on CBL Mariner 2.0
- azl3 tensorflow 2.16.1-9 on Azure Linux 3.0
- azl3 tensorflow 2.16.1-10 on Azure Linux 3.0
- azl3 python-tensorboard 2.16.2-6 on Azure Linux 3.0
- azl3 python-werkzeug 3.0.3-2 on Azure Linux 3.0
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21860
- https://nvd.nist.gov/vuln/detail/CVE-2026-21860
This medium severity vulnerability with a CVSS score of 5.3 was published on 2026-01-13 via Microsoft. Affected: cbl2 python-tensorboard 2.11.0-3 on CBL Mariner 2.0, cbl2 python-werkzeug 2.3.7-3 on CBL Mariner 2.0, azl3 tensorflow 2.16.1-9 on Azure Linux 3.0 and 3 more.
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