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CVE-2026-4890

Status: Awaiting AnalysisHigh (7.5)—

A Denial of Service (DoS) vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a crafted DNS packet.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vector AV:N/PR:N/UI:N indica red sin privilegios. Paquete DNS artesanal causa DoS (denegación de servicio) en dnsmasq remoto, típico de T1499.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Filter Network TrafficVulnerability ScanningPrivileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkApplication Isolation and Sandboxing

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Dnsmasq — DnsmasqAI

CWEs

References

Raw JSON (NVD)

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{
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      "url": "https://github.com/NixOS/nixpkgs/pull/519082",
      "source": "cret@cert.org"
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      "url": "https://github.com/NixOS/nixpkgs/pull/519093",
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      "url": "https://github.com/pi-hole/FTL/releases/tag/v6.6.2",
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      "value": "A Denial of Service (DoS) vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a crafted DNS packet."
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  ],
  "lastModified": "2026-08-25T13:19:21.320",
  "sourceIdentifier": "cret@cert.org"
}