FKIE_CVE-2026-40356

Vulnerability from fkie_nvd - Published: 2026-04-28 07:16 - Updated: 2026-04-28 20:11
Severity ?
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
In MIT Kerberos 5 (aka krb5) before 1.22.3, there is an integer underflow and resultant out-of-bounds read if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, possibly causing the process to terminate in parse_message.
References
cve@mitre.orghttps://cems.fun/2026/04/27/krb5-two-unauthenticated-network-vulnerabilities.html
cve@mitre.orghttps://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f
cve@mitre.orghttps://web.mit.edu/kerberos/advisories/
Impacted products
Vendor Product Version
To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In MIT Kerberos 5 (aka krb5) before 1.22.3, there is an integer underflow and resultant out-of-bounds read if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, possibly causing the process to terminate in parse_message."
    }
  ],
  "id": "CVE-2026-40356",
  "lastModified": "2026-04-28T20:11:56.713",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 5.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 3.6,
        "source": "cve@mitre.org",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-04-28T07:16:03.197",
  "references": [
    {
      "source": "cve@mitre.org",
      "url": "https://cems.fun/2026/04/27/krb5-two-unauthenticated-network-vulnerabilities.html"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://web.mit.edu/kerberos/advisories/"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-191"
        }
      ],
      "source": "cve@mitre.org",
      "type": "Primary"
    }
  ]
}


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