Botan is a C++ cryptography library.
CVE-2026-118769
Botan is a C++ cryptography library. From 2.1.0 until 3.13.0, the Botan C API function botanblockcipherblocksize converted a sizet block size to int without a bounds check. In an application that accepts external algorithm parameter strings and uses the FFI raw ECB mode, an attacker can select the variable-block-size Lion cipher so that the reported size is truncated, the caller allocates insufficient memory, and later block processing causes memory corruption. The C++ API and normally used C API modes such as CBC and CTR are unaffected. This issue is fixed in version 3.13.0.
Assessment
- CVSS
- 9.2 (v4.0)
- Severity
- Critical
- Known exploited
- Not listed in CISA KEV
- Exploit availability
- Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
- Published
- 29 October 2026
- Last updated
- 30 October 2026
- Weakness
- CWE-125, CWE-681, CWE-787
- Assigner
- security-advisories@github.com
CVSS vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
At the source
References
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