llama.cpp — security advisory

{
  "id": "e6b19310da038093f61c08c104bff7cbe4d7a1b9aaef792de0e4a88828583e74",
  "url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-43628",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "UBUNTU-CVE-2026-43628",
    "summary": "llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.",
    "evidence": "osv:UBUNTU-CVE-2026-43628",
    "products": [
      {
        "name": {
          "value": "llama.cpp",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "8681+dfsg-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "9721+dfsg-1ubuntu1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "10438+dfsg-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "10438+dfsg-1ubuntu1",
            "evidence": "/affected/0/versions"
          }
        ]
      },
      {
        "name": {
          "value": "llama.cpp",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "5882+dfsg-2",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "8064+dfsg-1ubuntu1",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "8681+dfsg-1",
            "evidence": "/affected/1/versions"
          }
        ]
      }
    ],
    "severity": "high",
    "structured": {
      "id": "UBUNTU-CVE-2026-43628",
      "aliases": [
        "UBUNTU-CVE-2026-43628"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"
        },
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
        },
        {
          "type": "Ubuntu",
          "score": "medium"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "llama.cpp",
            "purl": "pkg:deb/ubuntu/llama.cpp?arch=source&distro=stonking",
            "ecosystem": "Ubuntu:26.10"
          },
          "versions": [
            "8681+dfsg-1",
            "9721+dfsg-1ubuntu1",
            "10438+dfsg-1",
            "10438+dfsg-1ubuntu1"
          ],
          "database_specific": {
            "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43628.json"
          },
          "ecosystem_specific": {
            "binaries": [
              {
                "binary_name": "libllama0",
                "binary_version": "10438+dfsg-1ubuntu1"
              },
              {
                "binary_name": "llama.cpp",
                "binary_version": "10438+dfsg-1ubuntu1"
              },
              {
                "binary_name": "llama.cpp-examples",
                "binary_version": "10438+dfsg-1ubuntu1"
              },
              {
                "binary_name": "llama.cpp-services",
                "binary_version": "10438+dfsg-1ubuntu1"
              },
              {
                "binary_name": "llama.cpp-tests",
                "binary_version": "10438+dfsg-1ubuntu1"
              },
              {
                "binary_name": "llama.cpp-tools",
                "binary_version": "10438+dfsg-1ubuntu1"
              },
              {
                "binary_name": "llama.cpp-tools-extra",
                "binary_version": "10438+dfsg-1ubuntu1"
              },
              {
                "binary_name": "python3-gguf",
                "binary_version": "10438+dfsg-1ubuntu1"
              }
            ]
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "llama.cpp",
            "purl": "pkg:deb/ubuntu/llama.cpp?arch=source&distro=resolute",
            "ecosystem": "Ubuntu:26.04:LTS"
          },
          "versions": [
            "5882+dfsg-2",
            "8064+dfsg-1ubuntu1",
            "8681+dfsg-1"
          ],
          "database_specific": {
            "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43628.json"
          },
          "ecosystem_specific": {
            "binaries": [
              {
                "binary_name": "libllama0",
                "binary_version": "8681+dfsg-1"
              },
              {
                "binary_name": "llama.cpp",
                "binary_version": "8681+dfsg-1"
              },
              {
                "binary_name": "llama.cpp-examples",
                "binary_version": "8681+dfsg-1"
              },
              {
                "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"
              }
            ]
          }
        }
      ],
      "modified": "2026-10-17T12:58:55.421527629Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-43628"
      ],
      "references": [
        "https://ubuntu.com/security/CVE-2026-43628",
        "https://www.cve.org/CVERecord?id=CVE-2026-43628",
        "https://github.com/Vladimir-tokarev-cyera/llama-cpp-security-patches"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-43628",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/1/score"
  },
  "source_id": "core-osv",
  "document_id": 359173,
  "published_at": "2026-08-06T22:17:00+00:00"
}