CVE-2025-21602: Junos OS and Junos OS Evolved: Receipt of specially crafted BGP update packet causes RPD crash

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-01-09 · updated 2026-06-17
Weakness: CWE-755

Description

An Improper Handling of Exceptional Conditions vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker sending a specific BGP update packet to cause rpd to crash and restart, resulting in a Denial of Service (DoS). Continuous receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue affects iBGP and eBGP, and both IPv4 and IPv6 are affected by this vulnerability. This issue affects Junos OS: * from 21.4 before 21.4R3-S9, * from 22.2 before 22.2R3-S5, * from 22.3 before 22.3R3-S4, * from 22.4 before 22.4R3-S5, * from 23.2 before 23.2R2-S3, * from 23.4 before 23.4R2-S3, * from 24.2 before 24.2R1-S2, 24.2R2; This issue does not affect versions prior to 21.1R1. Junos OS Evolved: * from 21.4 before 21.4R3-S9-EVO, * from 22.2 before 22.2R3-S5-EVO, * from 22.3 before 22.3R3-S4-EVO, * from 22.4 before 22.4R3-S5-EVO, * from 23.2 before 23.2R2-S3-EVO, * from 23.4 before 23.4R2-S3-EVO, * from 24.2 before 24.2R1-S2-EVO, 24.2R2-EVO. This issue does not affect versions prior to 21.1R1-EVO

Affected products

Juniper Junos OS: 21.2, 21.2-r1, 21.2-r1-s1, 21.2-r1-s2, 21.2-r2, 21.2-r2-s1 (+79)
Juniper Networks Junos OS Evolved: 21.2, 21.2-r1, 21.2-r1-s1, 21.2-r1-s2, 21.2-r2, 21.2-r2-s1 (+78)

References

https://supportportal.juniper.net/JSA92872

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