CVE-2025-26465
Full vulnerability record from the local CVENow database.
Description
A vulnerability was found in OpenSSH when the VerifyHostKeyDNS option is enabled. A machine-in-the-middle attack can be performed by a malicious machine impersonating a legit server. This issue occurs due to how OpenSSH mishandles error codes in specific conditions when verifying the host key. For an attack to be considered successful, the attacker needs to manage to exhaust the client's memory resource first, turning the attack complexity high.
Severity
MEDIUM
CVSS score
6.8
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2025-02-18 19:15:29.230000
Last modified
2026-10-21 21:17:31.587000
View original CVE JSON
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"sourceIdentifier": "[email protected]",
"published": "2025-02-18T19:15:29.230",
"lastModified": "2026-10-21T21:17:31.587",
"vulnStatus": "Modified",
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"value": "Se encontró una vulnerabilidad en OpenSSH cuando la opción VerifyHostKeyDNS está habilitada. Un ataque de máquina en el medio puede ser realizado mediante una máquina maliciosa que se hace pasar por un servidor legítimo. Este problema ocurre debido a cómo los códigos de error de OpenSSH Mishandles en condiciones específicas al verificar la clave del host. Para que un ataque se considere exitoso, el atacante debe lograr agotar el recurso de memoria del cliente primero, lo que gira la complejidad del ataque."
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