{"id":"UBUNTU-CVE-2026-118769","details":"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.","modified":"2026-11-05T04:42:51Z","published":"2026-10-29T18:17:00Z","upstream":["CVE-2026-118769"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-118769"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-118769"},{"type":"REPORT","url":"https://github.com/randombit/botan/commit/c6089ab7fab616517d56c447c93e13a5c57a0af3"},{"type":"REPORT","url":"https://github.com/randombit/botan/pull/5805"},{"type":"REPORT","url":"https://github.com/randombit/botan/security/advisories/GHSA-c68p-822g-jfvr"}],"affected":[{"package":{"name":"botan","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/botan?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.4.0-3","2.4.0-4","2.4.0-5ubuntu1"],"ecosystem_specific":{"binaries":[{"binary_name":"botan","binary_version":"2.4.0-5ubuntu1"},{"binary_name":"libbotan-2-4","binary_version":"2.4.0-5ubuntu1"},{"binary_version":"2.4.0-5ubuntu1","binary_name":"python3-botan"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-118769.json"}},{"package":{"name":"botan","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/botan?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.9.0-2","2.9.0-2build1","2.12.1-2","2.12.1-2build1"],"ecosystem_specific":{"binaries":[{"binary_name":"botan","binary_version":"2.12.1-2build1"},{"binary_name":"libbotan-2-12","binary_version":"2.12.1-2build1"},{"binary_version":"2.12.1-2build1","binary_name":"python3-botan"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-118769.json"}},{"package":{"name":"botan","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/botan?arch=source&distro=esm-apps%2Fjammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.17.3+dfsg-3","2.19.1+dfsg-2ubuntu1","2.19.1+dfsg-2ubuntu1+esm1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.19.1+dfsg-2ubuntu1+esm1","binary_name":"botan"},{"binary_version":"2.19.1+dfsg-2ubuntu1+esm1","binary_name":"libbotan-2-19"},{"binary_version":"2.19.1+dfsg-2ubuntu1+esm1","binary_name":"python3-botan"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-118769.json"}},{"package":{"name":"botan","ecosystem":"Ubuntu:Pro:24.04:LTS","purl":"pkg:deb/ubuntu/botan?arch=source&distro=esm-apps%2Fnoble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.19.3+dfsg-1ubuntu1","2.19.3+dfsg-1ubuntu2","2.19.3+dfsg-1ubuntu2+esm1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.19.3+dfsg-1ubuntu2+esm1","binary_name":"botan"},{"binary_version":"2.19.3+dfsg-1ubuntu2+esm1","binary_name":"libbotan-2-19"},{"binary_name":"python3-botan","binary_version":"2.19.3+dfsg-1ubuntu2+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-118769.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}