CVE-2024-39513: Junos OS Evolved: Execution of a specific CLI command will cause a crash in the AFT manager

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-07-10 · updated 2026-06-17
Weakness: CWE-20

Description

An Improper Input Validation vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved allows a local, low-privileged attacker to cause a Denial of Service (DoS). When a specific "clear" command is run, the Advanced Forwarding Toolkit manager (evo-aftmand-bt or evo-aftmand-zx) crashes and restarts. The crash impacts all traffic going through the FPCs, causing a DoS. Running the command repeatedly leads to a sustained DoS condition. This issue affects Junos OS Evolved: * All versions before 20.4R3-S9-EVO, * from 21.2-EVO before 21.2R3-S7-EVO, * from 21.3-EVO before 21.3R3-S5-EVO, * from 21.4-EVO before 21.4R3-S6-EVO, * from 22.1-EVO before 22.1R3-S4-EVO, * from 22.2-EVO before 22.2R3-S3-EVO, * from 22.3-EVO before 22.3R3-S3-EVO, * from 22.4-EVO before 22.4R3-EVO, * from 23.2-EVO before 23.2R2-EVO.

Affected products

Juniper Networks Junos OS Evolved: before 20.4; 20.4, 20.4-r1, 20.4-r1-s1, 20.4-r1-s2, 20.4-r2, 20.4-r2-s1 (+90) — fixed in 20.4

How to fix

Upgrade to a fixed version: Juniper Networks Junos OS Evolved 20.4. Check the vendor advisory for mitigations.

References

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