CVE-2025-52952

Junos OS: MX Series with MPC-BUILTIN, MPC 1 through MPC 9: Receipt and processing of a malformed packet causes one or more FPCs to crash

MEDIUM

6.5

CVSS Score

Published: July 11, 2025 at 03:04 PM UTC

Updated: June 17, 2026 at 09:37 AM UTC

1 product affected across 1 vendorJunos

Using Junos OS by Juniper Networks?

Get instant alerts when new vulnerabilities affect Junos OS - before attackers find them.

Real-time alertsTrack your software stackFree plan available

Start Free Sign In

Severity

MEDIUM6.5

Exploit prediction

EPSS 0.3%

SSVC

No known exploit

Description

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Junos · Juniper Networks

95%

v < 22.2v < 22.2R3-S122.4 ≤ v < 22.4R222.2 22.2 r1 22.2 r1-s1 22.2 r1-s2 22.2 r2 22.2 r2-s1 22.2 r2-s2 22.2 r3 22.4 22.4 r1 22.4 r1-s1 22.4 r1-s2

Affected range stops below 22.2R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.4R2, so it looks safe — our inference, not a vendor statement

juniper-2x100ge-4x10ge-mpc5e (environment) · juniper-2x100ge-4x10ge-mpc5eq (environment) · juniper-2x100ge-8x10ge-mpc4e (environment) · juniper-32x10ge-mpc4e (environment) · juniper-6x40ge-24x10ge-mpc5e (environment) · juniper-6x40ge-24x10ge-mpc5eq (environment) · juniper-mpc1 (environment) · juniper-mpc1-q (environment) · juniper-mpc1e (environment) · juniper-mpc1e-q (environment) · juniper-mpc2 (environment) · juniper-mpc2-eq (environment) · juniper-mpc2-q (environment) · juniper-mpc2e (environment) · juniper-mpc2e-eq (environment) · juniper-mpc2e-ng (environment) · juniper-mpc2e-ng-q (environment) · juniper-mpc2e-p (environment) · juniper-mpc2e-q (environment) · juniper-mpc3e (environment) · juniper-mpc3e-3d-ng (environment) · juniper-mpc3e-3d-ng-q (environment) · juniper-mpc6e (environment) · juniper-mpc7e-10g (environment) · juniper-mpc7e-mrate (environment) · juniper-mpc8e (environment) · juniper-mpc9e (environment) · juniper-mx2008 (environment) · juniper-mx2010 (environment) · juniper-mx2020 (environment) · juniper-mx240 (environment) · juniper-mx480 (environment) · juniper-mx960 (environment)