CVE-2025-21597

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Juniper NetworksJunos OS0 < 20.4R3-S8affected
Juniper NetworksJunos OS21.2 < 21.2R3-S6affected
Juniper NetworksJunos OS21.3 < 21.3R3-S5affected
Juniper NetworksJunos OS21.4 < 21.4R3-S4affected
Juniper NetworksJunos OS22.1 < 22.1R3-S3affected
Juniper NetworksJunos OS22.2 < 22.2R3-S1affected
Juniper NetworksJunos OS22.3 < 22.3R3affected
Juniper NetworksJunos OS22.4 < 22.4R3affected
Juniper NetworksJunos OS Evolved0 < 21.2R3-S6-EVOaffected
Juniper NetworksJunos OS Evolved21.3-EVO < 21.3R3-S5-EVOaffected
Juniper NetworksJunos OS Evolved21.4-EVO < 21.4R3-S4-EVOaffected
Juniper NetworksJunos OS Evolved22.1-EVO < 22.1R3-S3-EVOaffected
Juniper NetworksJunos OS Evolved22.2-EVO < 22.2R3-S1-EVOaffected
Juniper NetworksJunos OS Evolved22.3-EVO < 22.3R3-EVOaffected
Juniper NetworksJunos OS Evolved22.4-EVO < 22.4R3-EVOaffected

Weaknesses

  • CWE-754: CWE-754 Improper Check for Unusual or Exceptional Conditions

Workarounds

There are no known workarounds for this issue.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References