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

Published Jul 9, 2026 CVSS 4.0 · 6.8 Medium EPSS < 1% KEV · Not listed
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.

Remediation

Vendor Solution

The following software releases have been updated to resolve this specific issue: Junos OS: 23.2R2-S7, 23.4R2-S7, 24.2R2, 24.4R1-S2, 24.4R2, 25.2R1, and all subsequent releases; Junos OS Evolved: 23.2R2-S7-EVO, 23.4R2-S8-EVO, 24.2R2-EVO, 24.4R1-S3-EVO, 24.4R2-EVO, 25.2R1-EVO, and all subsequent releases.


Vendor Workaround

There are no known workarounds for this issue. To reduce the risk of exploitation use access lists or firewall filters to limit access to the CLI only from trusted hosts and administrators.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
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' 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. 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.
Title Junos OS and Junos OS Evolved: EX Series, QFX Series, MX Series: A specific 'show l2-learning' command causes l2ald crash Junos OS and Junos OS Evolved: EX Series, QFX Series, MX Series: A specific 'show l2-learning/ethernet-switching' command causes l2ald crash
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Juniper Networks
Juniper Networks junos Os
Juniper Networks junos Os Evolved
Vendors & Products Juniper Networks
Juniper Networks junos Os
Juniper Networks junos Os Evolved
Type Values Removed Values Added
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' 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.
Title Junos OS and Junos OS Evolved: EX Series, QFX Series, MX Series: A specific 'show l2-learning' command causes l2ald crash
Weaknesses CWE-466
References
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 6.8, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/RE:M'}