Junos OS: MX Series with SPC3, SRX Series: Processing of a specifically malformed SIP invite causes a flowd crash
Summary
| CVE | CVE-2026-57026 |
|---|---|
| State | PUBLISHED |
| Assigner | juniper |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-09 22:17:07 UTC |
| Updated | 2026-07-10 17:49:57 UTC |
| 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. |
Risk And Classification
Primary CVSS: v4.0 8.7 HIGH from [email protected]
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/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
EPSS: 0.004610000 probability, percentile 0.368980000 (date 2026-07-11)
Problem Types: CWE-1286 | CWE-1286 CWE-1286 Improper Validation of Syntactic Correctness of Input
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 8.7 | HIGH | 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/E:X/C... |
| 4.0 | CNA | CVSS | 8.7 | HIGH | 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/... |
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v4.0 Breakdown
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/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
CVSS v3.1 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Juniper Networks | Junos OS | affected 23.2R2-S7 custom | SRX Series, MX Series with SPC3 |
| CNA | Juniper Networks | Junos OS | affected 23.4 23.4R2-S8 custom | SRX Series, MX Series with SPC3 |
| CNA | Juniper Networks | Junos OS | affected 24.2 24.2R2-S5 custom | SRX Series, MX Series with SPC3 |
| CNA | Juniper Networks | Junos OS | affected 24.4 24.4R2-S4 custom | SRX Series, MX Series with SPC3 |
| CNA | Juniper Networks | Junos OS | affected 25.2 25.2R2 custom | SRX Series, MX Series with SPC3 |
| CNA | Juniper Networks | Junos OS | affected 25.4 25.4R1-S2 custom | SRX Series, MX Series with SPC3 |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| supportportal.juniper.net/JSA110086 | [email protected] | supportportal.juniper.net | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Additional Advisory Data
Solutions
CNA: The following software releases have been updated to resolve this specific issue: Junos OS: 23.2R2-S7, 23.4R2-S8, 24.2R2-S5, 24.4R2-S4, 25.2R2, 25.4R1-S2, 25.4R2, 26.2R1, and all subsequent releases.
Workarounds
CNA: There are no known workarounds for this issue. To reduce the risk of exploitation customers not requiring the SIP ALG functionality could explicitly disable it (in case it's by default enabled) by configuring: [ security alg sip disable ]
Exploits
CNA: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.