CVE-2026-0966
Full vulnerability record from the local CVENow database.
Description
A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to `SSH_LOG_PACKET (3)` or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process.
Severity
HIGH
CVSS score
8.2
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-03-26 21:17:00.783000
Last modified
2026-11-05 17:17:27.390000
View original CVE JSON
{
"id": "CVE-2026-0966",
"sourceIdentifier": "[email protected]",
"published": "2026-03-26T21:17:00.783",
"lastModified": "2026-11-05T17:17:27.390",
"vulnStatus": "Modified",
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"value": "A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to `SSH_LOG_PACKET (3)` or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process."
},
{
"lang": "es",
"value": "La función API 'ssh_get_hexa()' es vulnerable cuando se proporciona una entrada de longitud 0 a esta función. Esta función se utiliza internamente en 'ssh_get_fingerprint_hash()' y 'ssh_print_hexa()' (obsoleta), la cual es vulnerable a la misma entrada (la longitud es proporcionada por la aplicación que realiza la llamada).\n\nLa función también se utiliza internamente en el código gssapi para registrar los OID recibidos por el servidor durante la autenticación GSSAPI. Esto podría activarse de forma remota cuando el servidor permite la autenticación GSSAPI y la verbosidad del registro se establece al menos en SSH_LOG_PACKET (3). Esto podría causar un auto-DoS del proceso demonio por conexión."
}
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"affected": [
{
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"description": [
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"references": [
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"source": "[email protected]"
},
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}