CVE-2026-57026CWE-1286

Junos OS: MX Series with SPC3, SRX Series: Processing of a specifically malformed SIP invite causes a flowd crash

High · published July 9, 2026

CVSS v4.0
8.7
EPSS
0%
Percentile
38.9
In the wild
Unconfirmed
What it is

An Improper Validation of Syntactic Correctness of Input vulnerability in the SIP plugin of Juniper Networks Junos OS on MX Series with SPC3 and SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).If the SIP ALG is enabled on an affected device, the processing of a malformed SIP invite packet will cause a flow processing daemon (flowd) crash and restart. This leads to a complete service outage until the system has automatically recovered.

This issue affects Junos OS on MX Series with SPC3 and SRX Series:

* all versions before 23.2R2-S7,

* 23.4 versions before 23.4R2-S8,

* 24.2 versions before 24.2R2-S5,

* 24.4 versions before 24.4R2-S4,

* 25.2 versions before 25.2R2,

* 25.4 versions before 25.4R1-S2.

The record
Technical detail
CVSS v4.0
8.7 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/RE:M
EPSS
0.00460 · 38.9th percentile
Weakness
CWE-1286 · Improper Validation of Syntactic Correctness of Input
Published
2026-07-09T21:07Z
EPSS history
Timeline
  • 09 JUL 21:07Z
    Junos OS: MX Series with SPC3, SRX Series: Processing of a specifically malformed SIP invite causes a flowd crash
    cvelistv5