CVE-2026-3446 (GCVE-0-2026-3446)

Vulnerability from cvelistv5 – Published: 2026-04-10 18:17 – Updated: 2026-04-13 16:07
VLAI
Title
Base64 decoding stops at first padded quad by default
Summary
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.
Severity
6 (Medium)
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-13 16:06 UTC
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
Assigner
PSF CNA under the mitre root
CNA scorecard B 80/100 over 28 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Python Software Foundation CPython Affected: 0 , < 3.13.13 (python)
Affected: 3.14.0 , < 3.14.4 (python)
Affected: 3.15.0a1 , < 3.15.0a8 (python)
guessed Create a notification for this product.
Credits
Serhiy Storchaka
Show details on NVD website
To clipboard 

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}



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