Junos OS and Junos OS Evolved: An unauthenticated adjacent attacker sending a valid BGP UPDATE packet forces a BGP session reset

Summary

An Expected Behavior Violation vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker sending a valid BGP UPDATE packet to cause a BGP session reset, 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: • All versions before 21.2R3-S9, • from 21.4 before 21.4R3-S11, • from 22.2 before 22.2R3-S7, • from 22.4 before 22.4R3-S7, • from 23.2 before 23.2R2-S4, • from 23.4 before 23.4R2-S4, • from 24.2 before 24.2R2, • from 24.4 before 24.4R1-S3, 24.4R2 Junos OS Evolved: • All versions before 22.2R3-S7-EVO, • from 22.4-EVO before 22.4R3-S7-EVO, • from 23.2-EVO before 23.2R2-S4-EVO, • from 23.4-EVO before 23.4R2-S4-EVO, • from 24.2-EVO before 24.2R2-EVO, • from 24.4-EVO before 24.4R1-S3-EVO, 24.4R2-EVO.

Timeline

1. Jul 11, 2025, 3:04 PM UTCCVE published
2. Jul 11, 2025, 8:11 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Jul 11, 2025, 8:11 PM UTCRecord last updated

Affected versions

• Juniper Networks Junos OS

  fixed in 21.2R3-S9; From 21.4 · fixed in 21.4R3-S11; From 22.2 · fixed in 22.2R3-S7; From 22.4 · fixed in 22.4R3-S7; From 23.2 · fixed in 23.2R2-S4; From 23.4 · fixed in 23.4R2-S4; From 24.2 · fixed in 24.2R2

• Juniper Networks Junos OS Evolved

  fixed in 22.2R3-S7-EVO; From 22.4-EVO · fixed in 22.4R3-S7-EVO; From 23.2-EVO · fixed in 23.2R2-S4-EVO; From 23.4-EVO · fixed in 23.4R2-S4-EVO; From 24.2-EVO · fixed in 24.2R2-EVO

References 2