CVE-2026-3446
mediumpriority · track · 0OT risk · elevatedEPSS 0.002 · 8 %ileDEEURUUSEPSS · scored 2026-10-29
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 2.3–6
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (33)
Products and version ranges known to be affected.
- Red Hat Enterprise Linux Update Infrastructure 5.1all versionscert_bundDEcpe:/o:redhat:enterprise_linux:update_infrastructure_5.1
advisories (5)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-1064CPython: Mehrere SchwachstellenDeutsch2026-04-12csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in CPython ausnutzen, um Sicherheitsvorkehrungen zu umgehen, und um Daten zu manipulieren.
- BIT-libpython-2026-3446Base64 decoding stops at first padded quad by default2026-04-16vendor · osvUS
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.
- BIT-python-2026-3446Base64 decoding stops at first padded quad by default2026-04-16vendor · osvUS
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.
- BIT-python-min-2026-3446Base64 decoding stops at first padded quad by default2026-04-16vendor · osvUS
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.
- PSF-2026-162026-04-10vendor · osvUS
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.
also known as (8)
Other names and identifiers for this entity.
- CNNVD-202604-2202cnnvd
- EUVD-2026-21545enisa_euvd
- BDU:2026-09712fstec_bdu
- GHSA-8r9f-h969-mm4menisa_euvd
- BIT-libpython-2026-3446osv
- BIT-python-2026-3446osv
- BIT-python-min-2026-3446osv
- PSF-2026-16osv
sources
Which sources assert this record, and when.
references (19)
External citations — patches, advisories, analysis.
- https://github.com/python/cpython/commit/1f9958f909c1b41a4ffc0b613ef8ec8fa5e7c474cnnvd
- https://github.com/python/cpython/commit/4561f6418a691b3e89aef0901f53fe0dfb7f7c0ecnnvd
- https://github.com/python/cpython/commit/e31c55121620189a0d1a07b689762d8ca9c1b7facnnvd
- https://github.com/python/cpython/issues/145264cnnvd
- https://github.com/python/cpython/pull/145267cnnvd
- https://mail.python.org/archives/list/security-announce@python.org/thread/F5ZT5ICGJ6CKXVUJ34YBVY7WOZ5SHG53/cnnvd
- https://www.python.org/downloads/Patchcnnvd
- https://github.com/python/cpython/commit/1f9958f909c1b41a4ffc0b613ef8ec8fa5e7c474enisa_euvd
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