An Improper Check for Unusual or Exceptional Conditions vulnerability in routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, logically adjacent BGP peer to cause Denial of Service (DoS).

On all Junos OS and Junos OS Evolved platforms, when BGP rib-sharding and update-threading are configured, and a BGP peer flap is done with specific timing, rpd crashes and restarts. Continuous peer flapping at specific time intervals will result in a sustained Denial of Service (DoS) condition.

This issue affects eBGP and iBGP, in both IPv4 and IPv6 implementations. This issue requires a remote attacker to have at least one established BGP session. The issue can occur with or without logical-systems enabled.

This issue affects:

Junos OS:

• All versions before 20.4R3-S8,
• 21.2 versions before 21.2R3-S6,
• 21.3 versions before 21.3R3-S5,
• 21.4 versions before 21.4R3-S4,
• 22.1 versions before 22.1R3-S3,
• 22.2 versions before 22.2R3-S1,
• 22.3 versions before 22.3R3,
• 22.4 versions before 22.4R3.

Junos OS Evolved:

• All versions before 21.2R3-S6-EVO,
• 21.3-EVO versions before 21.3R3-S5-EVO,
• 21.4-EVO versions before 21.4R3-S4-EVO,
• 22.1-EVO versions before 22.1R3-S3-EVO,
• 22.2-EVO versions before :22.2R3-S1-EVO,
• 22.3-EVO versions before 22.3R3-EVO,
• 22.4-EVO versions before 22.4R3-EVO.

For this issue to occur, BGP rib-sharding and update-threading needs to be configured:

[system processes routing bgp rib-sharding]

[system processes routing bgp update-threading]

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was seen during production usage.

The following software releases have been updated to resolve this specific issue:

Junos OS: 20.4R3-S8, 21.2R3-S6, 21.3R3-S5, 21.4R3-S4, 22.1R3-S3, 22.2R3-S1, 22.3R3, 22.4R3, 23.2R1, and all subsequent releases.

Junos OS Evolved: 21.2R3-S6-EVO, 21.3R3-S5-EVO, 21.4R3-S4-EVO, 22.1R3-S3-EVO, 22.2R3-S1-EVO, 22.3R3-EVO, 22.4R3-EVO, 23.2R1-EVO, and all subsequent releases.

This issue is being tracked as 1732833 which is visible on the Customer Support website.

Note: Juniper SIRT's policy is not to evaluate releases which are beyond End of Engineering (EOE) or End of Life (EOL).

There are no known workarounds for this issue.

2025-04-09: Initial Publication

2025-04-10: Added the missing CVE ID in title

2025-04-10: Corrected the CVSS scores

• KB16613: Overview of the Juniper Networks SIRT Quarterly Security Bulletin Publication Process [juniper.net]
• KB16765: In which releases are vulnerabilities fixed? [juniper.net]
• KB16446: Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories [juniper.net]
• Report a Security Vulnerability - How to Contact the Juniper Networks Security Incident Response Team