CVE-2024-21611: Junos OS and Junos OS Evolved: In a jflow scenario continuous route churn will cause a memory leak and eventually an rpd crash

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-01-12 · updated 2026-06-17
Weakness: CWE-401

Description

A Missing Release of Memory after Effective Lifetime 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). In a Juniper Flow Monitoring (jflow) scenario route churn that causes BGP next hops to be updated will cause a slow memory leak and eventually a crash and restart of rpd. Thread level memory utilization for the areas where the leak occurs can be checked using the below command: user@host> show task memory detail | match so_in so_in6 28 32 344450 11022400 344760 11032320 so_in 8 16 1841629 29466064 1841734 29467744 This issue affects: Junos OS * 21.4 versions earlier than 21.4R3; * 22.1 versions earlier than 22.1R3; * 22.2 versions earlier than 22.2R3. Junos OS Evolved * 21.4-EVO versions earlier than 21.4R3-EVO; * 22.1-EVO versions earlier than 22.1R3-EVO; * 22.2-EVO versions earlier than 22.2R3-EVO. This issue does not affect: Juniper Networks Junos OS versions earlier than 21.4R1. Juniper Networks Junos OS Evolved versions earlier than 21.4R1.

Affected products

Juniper Junos OS: 21.4, 21.4-r1, 21.4-r1-s1, 21.4-r1-s2, 21.4-r2, 21.4-r2-s1 (+15)
Juniper Networks Junos OS Evolved: 21.4, 21.4-r1, 21.4-r1-s1, 21.4-r1-s2, 21.4-r2, 21.4-r2-s1 (+13)

References

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