{"id":"UBUNTU-CVE-2026-2069","details":"A flaw has been found in ggml-org llama.cpp up to 55abc39. Impacted is the function llama_grammar_advance_stack of the file llama.cpp/src/llama-grammar.cpp of the component GBNF Grammar Handler. This manipulation causes stack-based buffer overflow. The attack needs to be launched locally. The exploit has been published and may be used. Patch name: 18993. To fix this issue, it is recommended to deploy a patch.","modified":"2026-05-20T16:24:09.187517008Z","published":"2026-02-06T22:16:00Z","upstream":["CVE-2026-2069"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-2069"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-2069"},{"type":"REPORT","url":"https://github.com/ggml-org/llama.cpp/"},{"type":"REPORT","url":"https://github.com/ggml-org/llama.cpp/issues/18988"},{"type":"REPORT","url":"https://github.com/ggml-org/llama.cpp/issues/18988#event-4426704865"},{"type":"REPORT","url":"https://github.com/ggml-org/llama.cpp/pull/18993"},{"type":"REPORT","url":"https://github.com/user-attachments/files/24761101/poc.zip"},{"type":"REPORT","url":"https://vuldb.com/?ctiid.344636"},{"type":"REPORT","url":"https://vuldb.com/?id.344636"},{"type":"REPORT","url":"https://vuldb.com/?submit.745263"}],"affected":[{"package":{"name":"llama.cpp","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/llama.cpp?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5318+dfsg-1","5318+dfsg-2","5713+dfsg-1","5760+dfsg-1","5760+dfsg-3","5760+dfsg-4","5882+dfsg-2"],"ecosystem_specific":{"binaries":[{"binary_version":"5882+dfsg-2","binary_name":"llama.cpp"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2069.json"}},{"package":{"name":"llama.cpp","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/llama.cpp?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5882+dfsg-2","8064+dfsg-1ubuntu1","8681+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_version":"8681+dfsg-1","binary_name":"libllama0"},{"binary_name":"llama.cpp","binary_version":"8681+dfsg-1"},{"binary_version":"8681+dfsg-1","binary_name":"llama.cpp-examples"},{"binary_name":"llama.cpp-tests","binary_version":"8681+dfsg-1"},{"binary_name":"llama.cpp-tools","binary_version":"8681+dfsg-1"},{"binary_name":"llama.cpp-tools-extra","binary_version":"8681+dfsg-1"},{"binary_name":"python3-gguf","binary_version":"8681+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2069.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P"},{"type":"Ubuntu","score":"medium"}]}