What’s Vulnerable › Vulnerabilities
CVE-2025-21596: Junos OS: SRX1500,SRX4100,SRX4200: Execution of low-privileged CLI command results in chassisd crash
- Severity: medium (CVSS 5.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2025-01-09 · updated 2026-06-17
- Weakness: CWE-755
Description
An Improper Handling of Exceptional Conditions vulnerability in the command-line processing of Juniper Networks Junos OS on SRX1500, SRX4100, and SRX4200 devices allows a local, low-privileged authenticated attacker executing the 'show chassis environment pem' command to cause the chassis daemon (chassisd) to crash and restart, resulting in a temporary Denial of Service (DoS). However, repeated execution of this command will eventually cause the chassisd process to fail to restart, impacting packet processing on the system. This issue affects Junos OS on SRX1500, SRX4100, SRX4200: * All versions before 21.4R3-S9, * from 22.2 before 22.2R3-S5, * from 22.3 before 22.3R3-S4, * from 22.4 before 22.4R3-S4, * from 23.2 before 23.2R2-S3, * from 23.4 before 23.4R2-S1.
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 (+56) — fixed in 21.4
How to fix
Upgrade to a fixed version: Juniper Junos OS 21.4. Check the vendor advisory for mitigations.
References
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