CVE-2026-118767

Botan: Python binding bcrypt APIs truncate passwords containing embedded NULs

Published Oct 29, 2026 CVSS 3.1 · 4.8 Medium EPSS < 1% KEV · Not listed
Description
Botan is a C++ cryptography library. From 1.11.22 until 3.13.0, Botan's Python binding converted Python strings containing U+0000 to const char* values without consistently rejecting the embedded NUL, causing bcrypt and check_bcrypt to process only the prefix before the NUL. Applications could validate a longer password but hash a shorter effective value, allowing application password-policy bypass; scrypt and argon2 are unaffected. This issue is fixed in version 3.13.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Randombit
Randombit botan
Vendors & Products Randombit
Randombit botan
Type Values Removed Values Added
Description Botan is a C++ cryptography library. From 1.11.22 until 3.13.0, Botan's Python binding converted Python strings containing U+0000 to const char* values without consistently rejecting the embedded NUL, causing bcrypt and check_bcrypt to process only the prefix before the NUL. Applications could validate a longer password but hash a shorter effective value, allowing application password-policy bypass; scrypt and argon2 are unaffected. This issue is fixed in version 3.13.0.
Title Botan: Python binding bcrypt APIs truncate passwords containing embedded NULs
Weaknesses CWE-158
References
Metrics cvssV3_1

{'score': 4.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 30, 2026, 5:12 PM
Reserved
Oct 28, 2026, 7:20 PM
Status
Awaiting Analysis
Published
Oct 29, 2026, 6:17 PM
Modified
Oct 30, 2026, 7:37 PM
Severity
Moderate
Public date
Oct 29, 2026, 5:17 PM