CVE-2025-52985

MEDIUM

Juniper Junos OS Evolved Firewall Bypass via Prefix List Operator Misuse

Title source: llm
STIX 2.1

Description

A Use of Incorrect Operator vulnerability in the Routing Engine firewall of Juniper Networks Junos OS Evolved allows an unauthenticated, network-based attacker to bypass security restrictions. When a firewall filter which is applied to the lo0 or re:mgmt interface references a prefix list with 'from prefix-list', and that prefix list contains more than 10 entries, the prefix list doesn't match and packets destined to or from the local device are not filtered. This issue affects firewall filters applied to the re:mgmt interfaces as input and output, but only affects firewall filters applied to the lo0 interface as output. This issue is applicable to IPv4 and IPv6 as a prefix list can contain IPv4 and IPv6 prefixes. This issue affects Junos OS Evolved: * 23.2R2-S3-EVO versions before 23.2R2-S4-EVO, * 23.4R2-S3-EVO versions before 23.4R2-S5-EVO, * 24.2R2-EVO versions before 24.2R2-S1-EVO, * 24.4-EVO versions before 24.4R1-S3-EVO, 24.4R2-EVO. This issue doesn't affect Junos OS Evolved versions before 23.2R1-EVO.

References (1)

Core 1
Core References
Vendor Advisory vendor-advisory
https://supportportal.juniper.net/JSA100091

Scores

CVSS v3 5.3
EPSS 0.0012
EPSS Percentile 30.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-480
Status published
Products (4)
juniper/junos_os_evolved 23.2 r2-s3
juniper/junos_os_evolved 23.4 r2-s3 (2 CPE variants)
juniper/junos_os_evolved 24.2 r2
juniper/junos_os_evolved 24.4 (4 CPE variants)
Published Jul 11, 2025
Tracked Since Feb 18, 2026