CVE-2026-33797CWE-20

Junos OS and Junos OS Evolved: An attacker sending a specific genuine BGP packet causes a BGP reset

High · published April 9, 2026

CVSS v4.0
7.1
EPSS
0%
Percentile
18.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
7.1 · HIGH
Vector
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/V:C/RE:M/U:Green
EPSS
0.00269 · 18.1th percentile
Weakness
CWE-20 · Improper Input Validation
Published
2026-04-09T21:31Z
EPSS history
Timeline
  • 09 APR 21:31Z
    Junos OS and Junos OS Evolved: An attacker sending a specific genuine BGP packet causes a BGP reset
    cvelistv5