CVE-2026-3446mediumCWE-345

CVE-2026-3446: fallo de gravedad media en Python Software Foundation CPython

Base64 decoding stops at first padded quad by default

Publicada el · Actualizada el

Seguir esta CVE+ Monitorear CPython+ Monitorear python3.11

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

13Vexday Risk Score

Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.

ssvc Trackcvss 6epss 0.2%
When calling base64.b64decode() or related functions the decoding process would stop after encountering the first padded quad regardless of whether there was more information to be processed. This can lead to data being accepted which may be processed differently by other implementations. Use "validate=True" to enable stricter processing of base64 data.
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Productos afectados
Python Software Foundation · CPython
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