Junos OS and Junos OS Evolved: With BGP sharding enabled, change in indirect next-hop can cause RPD crash

An Access of Uninitialized Pointer vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved with BGP sharding configured allows an attacker triggering indirect next-hop updates, along with timing outside the attacker's control, to cause rpd to crash and restart, leading to a Denial of Service (DoS).

With BGP sharding enabled, triggering route resolution of an indirect next-hop (e.g., an IGP route change over which a BGP route gets resolved), may cause rpd to crash and restart. An attacker causing continuous IGP route churn, resulting in repeated route re-resolution, will increase the likelihood of triggering this issue, leading to a potentially extended DoS condition.

This issue affects:

Junos OS:

• all versions before 21.4R3-S6,
• from 22.1 before 22.1R3-S6,
• from 22.2 before 22.2R3-S3,
• from 22.3 before 22.3R3-S3,
• from 22.4 before 22.4R3,
• from 23.2 before 23.2R2;

Junos OS Evolved:

• all versions before 22.3R3-S3-EVO,
• from 22.4 before 22.4R3-EVO,
• from 23.2 before 23.2R2-EVO.

Versions before Junos OS 21.3R1 and Junos OS Evolved 21.3R1-EVO are unaffected by this issue.