ruby-llm — security advisory

{
  "id": "662554a81cf74b053b1195818042d229dfe21fa0321d39ee99d68072b77bd856",
  "url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-67987",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "UBUNTU-CVE-2026-67987",
    "summary": "crmne/ruby_llm at commit fa6f279847d6d7027814539d9c0dfc3bbdfd2a83 contains polynomial-time regular expression denial-of-service conditions in think-tag response parsing on Ruby 3.1.x. A malicious or anomalous model response containing many unterminated tags can cause excessive CPU consumption in two consecutive regular expressions and delay chat-completion processing",
    "evidence": "osv:UBUNTU-CVE-2026-67987",
    "products": [
      {
        "name": {
          "value": "ruby-llm",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "1.16.0-2",
            "evidence": "/affected/0/versions"
          }
        ]
      }
    ],
    "severity": "high",
    "structured": {
      "id": "UBUNTU-CVE-2026-67987",
      "aliases": [
        "UBUNTU-CVE-2026-67987"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        },
        {
          "type": "Ubuntu",
          "score": "medium"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "ruby-llm",
            "purl": "pkg:deb/ubuntu/ruby-llm?arch=source&distro=stonking",
            "ecosystem": "Ubuntu:26.10"
          },
          "versions": [
            "1.16.0-2"
          ],
          "database_specific": {
            "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-67987.json"
          },
          "ecosystem_specific": {
            "binaries": [
              {
                "binary_name": "ruby-llm",
                "binary_version": "1.16.0-2"
              }
            ]
          }
        }
      ],
      "modified": "2026-10-17T13:00:40.031370956Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-67987"
      ],
      "references": [
        "https://ubuntu.com/security/CVE-2026-67987",
        "https://www.cve.org/CVERecord?id=CVE-2026-67987",
        "https://github.com/crmne/ruby_llm",
        "https://github.com/crmne/ruby_llm/blob/fa6f279847d6d7027814539d9c0dfc3bbdfd2a83/lib/ruby_llm/protocols/chat_completions/chat.rb#L355-L356",
        "https://github.com/crmne/ruby_llm/commit/5e88411f171721b381853fa77d254e266dcf6ad8"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-67987",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 360770,
  "published_at": "2026-09-29T20:17:00+00:00"
}