CVE-2026-33797
Full vulnerability record from the local CVENow database.
Description
An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS). An attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS: * 25.2 versions before 25.2R2 This issue does not affect Junos OS versions before 25.2R1. This issue affects Junos OS Evolved: * 25.2-EVO versions before 25.2R2-EVO This issue does not affect Junos OS Evolved versions before 25.2R1-EVO. eBGP and iBGP are affected. IPv4 and IPv6 are affected.
Severity
HIGH
CVSS score
7.1
(v4.0)
Vulnerability status
Modified
Source identifier
Published
2026-04-09 22:16:29.547000
Last modified
2026-10-26 22:10:00.163000
View original CVE JSON
{
"id": "CVE-2026-33797",
"sourceIdentifier": "[email protected]",
"published": "2026-04-09T22:16:29.547",
"lastModified": "2026-10-26T22:10:00.163",
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"value": "Una vulnerabilidad de validación de entrada incorrecta en Juniper Networks Junos OS y Junos OS Evolved permite a un atacante adyacente no autenticado, enviando un paquete BGP genuino específico en una sesión BGP ya establecida, restablecer solo esa sesión causando una denegación de servicio (DoS).\n\nUn atacante que envíe repetidamente el paquete mantendrá la denegación de servicio (DoS). Este problema afecta a Junos OS:\n\n * versiones 25.2 anteriores a 25.2R2\n\nEste problema no afecta a las versiones de Junos OS anteriores a 25.2R1.\n\nEste problema afecta a Junos OS Evolved:\n * versiones 25.2-EVO anteriores a 25.2R2-EVO\n\nEste problema no afecta a las versiones de Junos OS Evolved anteriores a 25.2R1-EVO.\n\neBGP e iBGP están afectados.\nIPv4 e IPv6 están afectados."
}
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"source": "[email protected]",
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"source": "[email protected]",
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}