CVE-2025-21600: Junos OS and Junos OS Evolved: With certain BGP options enabled, receipt of specifically malformed BGP update causes RPD crash
An Out-of-Bounds Read vulnerability in
the routing protocol daemon (rpd) of
Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, logically adjacent BGP peer sending a specifically malformed BGP packet to cause rpd to crash and restart, resulting in a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.
This issue only affects systems configured in either of two ways:
systems with BGP traceoptions enabled
systems with BGP family traffic-engineering (BGP-LS) configured
and can be exploited from a directly connected and configured BGP peer.
This issue affects iBGP and eBGP
with
any address family
configured, 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;
Junos OS Evolved:
from 21.4-EVO before 21.4R3-S9-EVO, from 22.2-EVO before 22.2R3-S5-EVO, from 22.3-EVO before 22.3R3-S4-EVO, from 22.4-EVO before 22.4R3-S5-EVO, from 23.2-EVO before 23.2R2-S3-EVO, from 23.4-EVO before 23.4R2-S2-EVO, from 24.2-EVO before 24.2R1-S2-EVO, 24.2R2-EVO.
This issue does not affect versions of Junos OS prior to 21.3R1.
This issue does not affect versions of Junos OS Evolved prior to 21.3R1-EVO.
This is a similar, but different vulnerability than the issue reported as CVE-2024-39516.
Affected Software
Remediation
Information
Event History
Frequently Asked Questions
What is the severity of CVE-2025-21600?
CVE-2025-21600 has a high severity rating due to its potential to cause crashes and unavailability of the routing protocol daemon.
How does CVE-2025-21600 affect Junos OS and Junos OS Evolved?
CVE-2025-21600 allows an unauthenticated BGP peer to send a malformed packet causing a denial of service by crashing the routing protocol daemon.
How do I fix CVE-2025-21600?
To fix CVE-2025-21600, apply the recommended software patches provided by Juniper Networks for the affected versions of Junos OS and Junos OS Evolved.
Who is affected by CVE-2025-21600?
Organizations using affected versions of Juniper Networks Junos OS and Junos OS Evolved are vulnerable to CVE-2025-21600.
What types of systems are impacted by CVE-2025-21600?
CVE-2025-21600 impacts systems running certain versions of Juniper Networks Junos OS and Junos OS Evolved, particularly those involving BGP peer configurations.