Botan: Integer overflow when reporting block size in FFI can cause memory corruption (randombit botan)

CVE-2026-118769
CRITICAL 9.2

At a glance

Source
NVD
EPSS
EPSS 0.36 % Β· percentile 30 ()
State
PUBLISHED
Published
Updated
Assigner
GitHub_M
NVD status
Awaiting Analysis

Description

Botan is a C++ cryptography library. From 2.1.0 until 3.13.0, the Botan C API function botan_block_cipher_block_size converted a size_t 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.

Weaknesses (CWE)

  • CWE-125 β€” Out-of-bounds Read
  • CWE-681 β€” Incorrect Conversion between Numeric Types
  • CWE-787 β€” Out-of-bounds Write

References

Scores

VersionScoreVectorScored by
CVSS 4.0CRITICAL 9.2CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NGitHub_M
CVSS 4.0CRITICAL 9.2CVSS: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:XNVD Β· security-advisories@github.com (Secondary)

European references

Affected products

ProductVersions
randombit Β· botanaffected >= 2.1.0, < 3.13.0

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST β€” attribution requested
ENISA EUVDENISA β€” reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain β€” this product uses data from the NVD API but is not endorsed or certified by the NVD