Vulnerability in Python Software Foundation Cpython
CVE-2026-3446
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.
EPSS: 0.002 (8.8th percentile) — read the EPSS interpretation.
Affected products
- Python Software Foundation Cpython — versions 0, 3.14.0, 3.15.0a1
Weakness classification (CWE)
References
- cna@python.org (patch)
- cna@python.org (issue-tracking)
- cna@python.org (vendor-advisory)
- cna@python.org (patch)
- cna@python.org (patch)
- cna@python.org (patch)