8.7
HIGH CVSS 4.0
CVE-2026-57026
Junos OS: MX Series with SPC3, SRX Series: Processing of a specifically malformed SIP invite causes a flowd crash
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.

INFO

Published Date :

July 9, 2026, 10:17 p.m.

Last Modified :

July 9, 2026, 10:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-57026 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 8cbe9d5a-a066-4c94-8978-4b15efeae968
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 8cbe9d5a-a066-4c94-8978-4b15efeae968
CVSS 4.0 HIGH [email protected]
Solution
Update Junos OS to a fixed version to prevent DoS from malformed SIP packets.
  • Update Junos OS to a fixed version.
  • Disable SIP ALG if possible.
  • Apply vendor patches promptly.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-57026.

URL Resource
https://supportportal.juniper.net/JSA110086
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-57026 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-57026 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-57026 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-57026 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 09, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Juniper Networks', 'product': 'Junos OS', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '23.2R2-S7', 'versionType': 'custom'}, {'status': 'affected', 'version': '23.4', 'lessThan': '23.4R2-S8', 'versionType': 'custom'}, {'status': 'affected', 'version': '24.2', 'lessThan': '24.2R2-S5', 'versionType': 'custom'}, {'status': 'affected', 'version': '24.4', 'lessThan': '24.4R2-S4', 'versionType': 'custom'}, {'status': 'affected', 'version': '25.2', 'lessThan': '25.2R2', 'versionType': 'custom'}, {'status': 'affected', 'version': '25.4', 'lessThan': '25.4R1-S2', 'versionType': 'custom'}], 'platforms': ['SRX Series', 'MX Series with SPC3'], 'defaultStatus': 'unaffected'}]
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:X/RE:M/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-1286
    Added Reference https://supportportal.juniper.net/JSA110086
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.