CVE-2025-52952: Juniper Junos

Medium severity, CVSS 6.5. EPSS: 0.3% chance of exploitation in the next 30 days.

An Out-of-bounds Write vulnerability in the connectivity fault management (CFM) daemon of Juniper Networks Junos OS on MX Series with MPC-BUILTIN, MPC1 through MPC9 line cards allows an unauthenticated adjacent attacker to send a malformed packet to the device, leading to an FPC crash and restart, resulting in a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks: Junos OS: * All versions before 22.2R3-S1, * from 22.4 before 22.4R2. This feature is not enabled by default.

Affected products

• Juniper Junos: before 22.2 (fixed in 22.2); version 22.2 only; version 22.4 only

Published 2025-07-11. Last modified 2026-06-17.