CVE-2024-39543: Junos OS and Junos OS Evolved: Receipt of a large RPKI-RTR PDU packet can cause rpd to crash

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-07-11 · updated 2026-06-17
Weakness: CWE-120

Description

A Buffer Copy without Checking Size of Input vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Juniper Networks Junos OS Evolved allows an unauthenticated, adjacent attacker to send specific RPKI-RTR packets resulting in a crash, creating a Denial of Service (DoS) condition. Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue affects Junos OS: * All versions before 21.2R3-S8, * from 21.4 before 21.4R3-S8, * from 22.2 before 22.2R3-S4, * from 22.3 before 22.3R3-S3, * from 22.4 before 22.4R3-S2, * from 23.2 before 23.2R2-S1, * from 23.4 before 23.4R2. Junos OS Evolved: * All versions before 21.2R3-S8-EVO, * from 21.4 before 21.4R3-S8-EVO, * from 22.2 before 22.2R3-S4-EVO, * from 22.3 before 22.3R3-S3-EVO, * from 22.4 before 22.4R3-S2-EVO, * from 23.2 before 23.2R2-S1-EVO, * from 23.4 before 23.4R2-EVO.

Affected products

Juniper Junos OS: before 21.2; 21.2, 21.2-r1, 21.2-r1-s1, 21.2-r1-s2, 21.2-r2, 21.2-r2-s1 (+63) — fixed in 21.2
Juniper Networks Junos OS Evolved: before 21.2; 21.2, 21.2-r1, 21.2-r1-s1, 21.2-r1-s2, 21.2-r2, 21.2-r2-s1 (+63) — fixed in 21.2

How to fix

Upgrade to a fixed version: Juniper Junos OS 21.2; Juniper Networks Junos OS Evolved 21.2. Check the vendor advisory for mitigations.

References

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