CVE-2026-57026

High

Description

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.

SeverityHigh
CVSS7.5
Exploit probability—
ProductJuniper Junos
PublishedJul 9, 2026
First seenJul 9, 2026
Weakness typeCWE-1286CWE-1286

How to fix

Update
  • juniper junos23.2 or later

Affected products

ProductAffected versionsFixed in
juniper junosv < 23.2, 23.2, 23.4, 24.2, 24.4, 25.2, 25.423.2

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