Question: What is CVE-2025-21593?
Answer: CVE-2025-21593 is a vulnerability classified as high with a CVSS score of 7.1. It falls under CWE-664 and affects the system as follows: An Improper Control of a Resource Through its Lifetime vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated network-based attacker to cause a Denial-of-Service (DoS).

On devices with SRv6 (Segment Routing over IPv6) enabled, an attacker can send a malformed BGP UPDATE packet which will cause the rpd to crash and restart. Continued receipt of these UPDATE packets will cause a sustained DoS condition. 

This issue affects iBGP and eBGP, and both IPv4 and IPv6 are affected by this vulnerability.This issue affects Junos OS: 



  *  All versions before 21.2R3-S9, 
  *  from 21.4 before 21.4R3-S10, 
  *  from 22.2 before 22.2R3-S5, 
  *  from 22.3 before 22.3R3-S4, 
  *  from 22.4 before 22.4R3-S3, 
  *  from 23.2 before 23.2R2-S2, 
  *  from 23.4 before 23.4R2;



and Junos OS Evolved: 



  *  All versions before 21.2R3-S9-EVO, 
  *  from 21.4-EVO before 21.4R3-S10-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-S3-EVO,
  *  from 23.2-EVO before 23.2R2-S2-EVO, 
  *  from 23.4-EVO before 23.4R2-EVO.