CVE-2026-107708 affecting package krb5 1.21.3-5

{
  "id": "4f954469addb75f47d92c68391e6d82a73c23b67884274708cab0c4792c2ac7a",
  "url": "https://osv.dev/vulnerability/AZL-106836",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-107708 affecting package krb5 1.21.3-5",
    "summary": "MIT krb5 through 1.22.2 contains a NULL pointer dereference vulnerability in the KDC's get_pac_princ_with_realm() that returns success while leaving the client principal NULL on malformed names. A malicious or compromised cross-realm trusted KDC can send an S4U2Proxy request with a PAC carrying a malformed client name to crash krb5kdc and deny authentication.",
    "evidence": "osv:AZL-106836",
    "products": [
      {
        "name": {
          "value": "krb5",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "AZL-106836",
      "aliases": [
        "AZL-106836"
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "1.21.3-5"
                }
              ]
            }
          ],
          "package": {
            "name": "krb5",
            "purl": "pkg:rpm/azure-linux/krb5",
            "ecosystem": "Azure Linux:3"
          },
          "database_specific": {
            "source": "https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-106836.json"
          }
        }
      ],
      "modified": "2026-10-15T05:37:09Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-107708"
      ],
      "references": [
        "https://nvd.nist.gov/vuln/detail/CVE-2026-107708"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-107708",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 321450,
  "published_at": "2026-10-08T21:17:52+00:00"
}