CVE-2026-5089 affecting package perl-YAML 1.30-2

{
  "id": "7edb61b32bb971d9b30dbde3f5a0d722564fcee6753871e810abb40e78c6783e",
  "url": "https://osv.dev/vulnerability/AZL-109511",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-5089 affecting package perl-YAML 1.30-2",
    "summary": "YAML::Syck versions before 1.38 for Perl has an out-of-bounds read. The base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer: while ( colon >= ptr && *colon != ':' ) { colon--; } if ( *colon == ':' ) *colon = '\\0'; // colon may be ptr-1 here When no colon is found (final/leftmost segment), colon becomes ptr-1, and the subsequent *colon dereference reads one byte before the allocated buffer.",
    "evidence": "osv:AZL-109511",
    "products": [
      {
        "name": {
          "value": "perl-YAML",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "AZL-109511",
      "aliases": [
        "AZL-109511"
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "1.30-2"
                }
              ]
            }
          ],
          "package": {
            "name": "perl-YAML",
            "purl": "pkg:rpm/azure-linux/perl-YAML",
            "ecosystem": "Azure Linux:3"
          },
          "database_specific": {
            "source": "https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-109511.json"
          }
        }
      ],
      "modified": "2026-10-27T05:36:16Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-5089"
      ],
      "references": [
        "https://nvd.nist.gov/vuln/detail/CVE-2026-5089"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-5089",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 460468,
  "published_at": "2026-05-12T17:16:21+00:00"
}