CVE-2026-57026Junos OS: MX Series with SPC3, SRX Series: Processing of a specifically malformed SIP invite causes a flowd crash
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.
Overview
Severity
| Score | Severity | Version | Vector String |
|---|---|---|---|
| 8.7 | HIGH | 4.0juniper (CNA) | 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 |
| 7.5 | HIGH | 3.1juniper (CNA) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Details
- CVE ID
- CVE-2026-57026
- Status
- Analyzed
- Assigner (CNA)
- juniper
- Published
- Jul 9, 2026
- Last modified
- 2026-10-25 15:10 UTC
- Weaknesses
- CWE-1286 · Improper Validation of Syntactic Correctness of Input
Affected Products
As published by the CNA in the CVE record.
Juniper NetworksJunos OS6 version ranges
- before 23.2R2-S7
- 23.4 before 23.4R2-S8
- 24.2 before 24.2R2-S5
- 24.4 before 24.4R2-S4
- 25.2 before 25.2R2
- 25.4 before 25.4R1-S2