CVE-2025-8277

A flaw was found in libssh's handling of key exchange (KEX) processes when a client repeatedly sends incorrect KEX guesses. The library fails to free memory during these rekey operations, which can gradually exhaust system memory. This issue can lead to crashes on the client side, particularly when using libgcrypt, which impacts application stability and availability.

CVSS v3 3.1 LOW

3.1^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:18683
https://access.redhat.com/security/cve/CVE-2025-8277
https://bugzilla.redhat.com/show_bug.cgi?id=2383888
https://www.libssh.org/security/advisories/CVE-2025-8277.txt

Configurations

No configuration.

History

18 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Se encontró una falla en el manejo de libssh de los procesos de intercambio de claves (KEX) cuando un cliente envía repetidamente suposiciones KEX incorrectas. La biblioteca no libera memoria durante estas operaciones de renegociación de clave, lo que puede agotar gradualmente la memoria del sistema. Este problema puede provocar fallos en el lado del cliente, particularmente al usar libgcrypt, lo que afecta la estabilidad y disponibilidad de la aplicación.

Information

Published : 2025-09-09 12:15

Updated : 2026-10-18 21:10

NVD link : CVE-2025-8277

Mitre link : CVE-2025-8277

CVE.ORG link : CVE-2025-8277

JSON object : View

Products Affected

No product.

CWE

CWE-401

Missing Release of Memory after Effective Lifetime

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The library fails to free memory during these rekey operations, which can gradually exhaust system memory. This issue can lead to crashes on the client side, particularly when using libgcrypt, which impacts application stability and availability."}, {"lang": "es", "value": "Se encontr\u00f3 una falla en el manejo de libssh de los procesos de intercambio de claves (KEX) cuando un cliente env\u00eda repetidamente suposiciones KEX incorrectas. La biblioteca no libera memoria durante estas operaciones de renegociaci\u00f3n de clave, lo que puede agotar gradualmente la memoria del sistema. Este problema puede provocar fallos en el lado del cliente, particularmente al usar libgcrypt, lo que afecta la estabilidad y disponibilidad de la aplicaci\u00f3n."}], "lastModified": "2026-10-18T21:10:00.120", "sourceIdentifier": "secalert@redhat.com"}