CVE-2024-39515: Junos OS and Junos OS Evolved: With BGP traceoptions enabled, receipt of specifically malformed BGP update causes RPD crash

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-10-09 · updated 2026-06-17
Weakness: CWE-1288

Description

An Improper Validation of Consistency within Input vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated network-based attacker sending a specifically malformed BGP packet to cause rpd to crash and restart, resulting in a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. In some cases, rpd fails to restart requiring a manual restart via the 'restart routing' CLI command. This issue only affects systems with BGP traceoptions enabled and requires a BGP session to be already established. Systems without BGP traceoptions enabled are not affected by this issue. This issue affects iBGP and eBGP, and both IPv4 and IPv6 are affected by this vulnerability. This issue affects: Junos OS: * All versions before 21.4R3-S8, * 22.2 before 22.2R3-S5, * 22.3 before 22.3R3-S4, * 22.4 before 22.4R3-S3, * 23.2 before 23.2R2-S2, * 23.4 before 23.4R2; Junos OS Evolved: * All versions before 21.4R3-S8-EVO, * 22.2-EVO before 22.2R3-S5-EVO, * 22.3-EVO before 22.3R3-S4-EVO, * 22.4-EVO before 22.4R3-S3-EVO, * 23.2-EVO before 23.2R2-S2-EVO, * 23.4-EVO before 23.4R2-EVO.

Affected products

Juniper Junos OS: before 21.4; 21.4, 21.4-r1, 21.4-r1-s1, 21.4-r1-s2, 21.4-r2, 21.4-r2-s1 (+53) — fixed in 21.4
Juniper Networks Junos OS Evolved: before 21.4; 21.4, 21.4-r1, 21.4-r1-s1, 21.4-r1-s2, 21.4-r2, 21.4-r2-s1 (+52) — fixed in 21.4

How to fix

Upgrade to a fixed version: Juniper Junos OS 21.4; Juniper Networks Junos OS Evolved 21.4. Check the vendor advisory for mitigations.

References

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