What’s Vulnerable › Vulnerabilities
CVE-2026-57025: Junos OS and Junos OS Evolved: EX Series, QFX Series, MX Series: A specific 'show l2-learning/ethernet-switching' command causes l2ald crash
- 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: 2026-07-09 · updated 2026-07-16
- Weakness: CWE-466
Description
A Return of Pointer Value Outside of Expected Range vulnerability in the fileio library of Juniper Networks Junos OS and Junos OS Evolved allows a local, low-privilged attacker to cause a Denial-of-Service (DoS). On EX Series, QFX Series and MX Series a low-privileged attacker issuing a specific 'show l2-learning' or 'show ethernet-switching' command will cause an l2ald crash which will lead to a temporary service impact for all layer 2 services until the process has automatically restarted. This issue affects EX Series, QFX Series, MX Series: Junos OS: * all versions before 23.2R2-S7, * 23.4 versions before 23.4R2-S7, * 24.2 versions before 24.2R2, * 24.4 versions before 24.4R1-S2. Junos OS Evolved: * all versions before 23.2R2-S7-EVO, * 23.4 versions before 23.4R2-S8-EVO, * 24.2 versions before 24.2R2-EVO, * 24.4 versions before 24.4R1-S3-EVO.
Affected products
- Juniper Junos OS: before 23.2; 23.2, 23.2-r1, 23.2-r1-s1, 23.2-r1-s2, 23.2-r2, 23.2-r2-s1 (+22) — fixed in 23.2
- Juniper Networks Junos OS Evolved: before 23.2; 23.2, 23.2-r1, 23.2-r1-s1, 23.2-r1-s2, 23.2-r2, 23.2-r2-s1 (+23) — fixed in 23.2
How to fix
Upgrade to a fixed version: Juniper Junos OS 23.2; Juniper Networks Junos OS Evolved 23.2. Check the vendor advisory for mitigations.
References
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