CVE-2023-0026

Summary

An Improper Input Validation 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). When a BGP update message is received over an established BGP session, and that message contains a specific, optional transitive attribute, this session will be torn down with an update message error. This issue cannot propagate beyond an affected system as the processing error occurs as soon as the update is received. This issue is exploitable remotely as the respective attribute can propagate through unaffected systems and intermediate AS (if any). Continuous receipt of a BGP update containing this attribute will create a sustained Denial of Service (DoS) condition. Some customers have experienced these BGP session flaps which prompted Juniper SIRT to release this advisory out of cycle before fixed releases are widely available as there is an effective workaround.

This issue affects: Juniper Networks Junos OS 15.1R1 and later versions prior to 20.4R3-S8; 21.1 version 21.1R1 and later versions prior to 21.2R3-S6; 21.3 versions prior to 21.3R3-S5; 21.4 versions prior to 21.4R3-S4; 22.1 versions prior to 22.1R3-S4; 22.2 versions prior to 22.2R3-S2; 22.3 versions prior to 22.3R2-S2, 22.3R3-S1; 22.4 versions prior to 22.4R2-S1, 22.4R3; 23.1 versions prior to 23.1R1-S1, 23.1R2.

Juniper Networks Junos OS Evolved All versions prior to 20.4R3-S8-EVO; 21.1 version 21.1R1-EVO and later versions prior to 21.2R3-S6-EVO; 21.3 versions prior to 21.3R3-S5-EVO; 21.4 versions prior to 21.4R3-S4-EVO; 22.1 versions prior to 22.1R3-S4-EVO; 22.2 versions prior to 22.2R3-S2-EVO; 22.3 versions prior to 22.3R2-S2-EVO, 22.3R3-S1-EVO; 22.4 versions prior to 22.4R2-S1-EVO, 22.4R3-EVO; 23.1 versions prior to 23.1R1-S1-EVO, 23.1R2-EVO.

Affected Software

VendorProductVersion RangeStatus
Juniper NetworksJunos OSunspecified < 15.1R1unaffected
Juniper NetworksJunos OSunspecified < 20.4R3-S8affected
Juniper NetworksJunos OS21.1 < 21.1*affected
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-S4affected
Juniper NetworksJunos OS22.2 < 22.3R2-S2, 22.3R3-S1affected
Juniper NetworksJunos OS22.3 < 22.2R3-S2affected
Juniper NetworksJunos OS22.4 < 22.4R2-S1, 22.4R3affected
Juniper NetworksJunos OS23.1 < 23.1R1-S1, 23.1R2affected
Juniper NetworksJunos OS Evolvedunspecified < 20.4R3-S8-EVOaffected
Juniper NetworksJunos OS Evolved21.1R1-EVO < 21.1*affected
Juniper NetworksJunos OS Evolved21.2 < 21.2R3-S6-EVOaffected
Juniper NetworksJunos OS Evolved21.3 < 21.3R3-S5-EVOaffected
Juniper NetworksJunos OS Evolved21.4 < 21.4R3-S4-EVOaffected
Juniper NetworksJunos OS Evolved22.1 < 22.1R3-S4-EVOaffected
Juniper NetworksJunos OS Evolved22.2 < 22.2R3-S2-EVOaffected
Juniper NetworksJunos OS Evolved22.3 < 22.3R2-S2-EVO, 22.3R3-S1-EVOaffected
Juniper NetworksJunos OS Evolved22.4 < 22.4R2-S1-EVO, 22.4R3-EVOaffected
Juniper NetworksJunos OS Evolved23.1 < 23.1R1-S1-EVO, 23.1R2-EVOaffected

Weaknesses

  • CWE-20: CWE-20 Improper Input Validation
  • Denial of Service (DoS)

Workarounds

The workaround is to configure BGP error tolerance by way of:

[ protocols bgp bgp-error-tolerance … ] which causes malformed BGP routes to be 'treated as withdrawal' instead of bringing down the BGP session. Additional details can be found at https://www.juniper.net/documentation/us/en/software/junos/bgp/topics/topic-map/bgp-error-messages.html

Juniper considers configuring this option to be a Best Common Practice (BCP) as it not only prevents this issue from happening, but protects against similar issues as well.

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References