Vulnerability · Published Jul 11, 2025 · Assigned by juniper

CVE-2025-52952Junos 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

In plain English

A medium-severity out-of-bounds write in Junos OS from Juniper Networks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 24% of all known vulnerabilities).

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.3%top 76.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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 products (as reported)

Vendor	Product	Versions
Juniper Networks	Junos OS	0 – before 22.2R3-S122.4 – before 22.4R2

Weakness: CWE-787 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://supportportal.juniper.net/JSA100058 vendor-advisory
https://www.juniper.net/documentation/us/en/software/junos/network-mgmt/topics/topic-map/cfm-configuring.html technical-description