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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-3446 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  Python Software Foundation
CVSS-B 6.0 MEDIUM
Vector:  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

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/python/cpython/commit/1f9958f909c1b41a4ffc0b613ef8ec8fa5e7c474 Python Software Foundation
https://github.com/python/cpython/commit/4561f6418a691b3e89aef0901f53fe0dfb7f7c0e Python Software Foundation
https://github.com/python/cpython/commit/e31c55121620189a0d1a07b689762d8ca9c1b7fa Python Software Foundation
https://github.com/python/cpython/issues/145264 Python Software Foundation
https://github.com/python/cpython/pull/145267 Python Software Foundation
https://mail.python.org/archives/list/[email protected]/thread/F5ZT5ICGJ6CKXVUJ34YBVY7WOZ5SHG53/ Python Software Foundation

Weakness Enumeration

CWE-ID CWE Name Source

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-3446
NVD Published Date:
04/10/2026
NVD Last Modified:
04/10/2026
Source:
Python Software Foundation