CVE-2026-33797 HIGH

CVE-2026-33797: Junos OS and Junos OS Evolved: An attacker sending a specific genuine BGP packet causes a BGP reset

Vendor Juniper Networks
Product Junos OS
Weakness CWE-20 · Input validation
Published April 9, 2026
Last update April 23, 2026
View on NVD All CVEs

CVSS base score

7.4/10
Attack vector Adjacent
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

April 9, 2026 CVE published
April 23, 2026 Record updated