CVE-2024-39551: Junos OS: SRX Series and MX Series with SPC3 and MS-MPC/MIC: Receipt of specific packets in H.323 ALG causes traffic drop

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: 2024-07-11 · updated 2026-06-17
Weakness: CWE-400

Description

An Uncontrolled Resource Consumption vulnerability in the H.323 ALG (Application Layer Gateway) of Juniper Networks Junos OS on SRX Series and MX Series with SPC3 and MS-MPC/MIC, allows an unauthenticated network-based attacker to send specific packets causing traffic loss leading to Denial of Service (DoS). Continued receipt and processing of these specific packets will sustain the Denial of Service condition. The memory usage can be monitored using the below command. user@host> show usp memory segment sha data objcache jsf This issue affects SRX Series and MX Series with SPC3 and MS-MPC/MIC: * 20.4 before 20.4R3-S10, * 21.2 before 21.2R3-S6, * 21.3 before 21.3R3-S5, * 21.4 before 21.4R3-S6, * 22.1 before 22.1R3-S4, * 22.2 before 22.2R3-S2, * 22.3 before 22.3R3-S1, * 22.4 before 22.4R3, * 23.2 before 23.2R2.

Affected products

Juniper Junos OS: 20.4, 20.4-r1, 20.4-r1-s1, 20.4-r2, 20.4-r2-s1, 20.4-r2-s2 (+87)

References

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