CVE-2025-30656
Junos OS: MX Series, SRX Series: Processing of specific SIP INVITE messages by the SIP ALG will lead to an FPC crash
- Published
- Updated
- Reserved
- Assigned by
- juniper
Description
An Improper Handling of Additional Special Element vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series with MS-MPC, MS-MIC and SPC3, and SRX Series, allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). If the SIP ALG processes specifically formatted SIP invites, a memory corruption will occur which will lead to a crash of the FPC processing these packets. Although the system will automatically recover with the restart of the FPC, subsequent SIP invites will cause the crash again and lead to a sustained DoS. This issue affects Junos OS on MX Series and SRX Series: * all versions before 21.2R3-S9, * 21.4 versions before 21.4R3-S10, * 22.2 versions before 22.2R3-S6, * 22.4 versions before 22.4R3-S5, * 23.2 versions before 23.2R2-S3, * 23.4 versions before 23.4R2-S3, * 24.2 versions before 24.2R1-S2, 24.2R2.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| juniperCNA (assigner) | 4.0 | High8.7 | 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 |
| juniperCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Analyzed | 4.0 | High8.7 | 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 (exploitation in 30 days)
- 0.43% · top 62% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.7.
Weakness
Affected products
- affected < 21.2R3-S9
- affected 21.4 – < 21.4R3-S10
- affected 22.2 – < 22.2R3-S6
- affected 22.4 – < 22.4R3-S5
- affected 23.2 – < 23.2R2-S3
- affected 23.4 – < 23.4R2-S3
- affected 24.2 – < 24.2R1-S2, 24.2R2
What to do
Solution: The following software releases have been updated to resolve this specific issue: 21.2R3-S9, 21.4R3-S10, 22.2R3-S6, 22.4R3-S5, 23.2R2-S3, 23.4R2-S3, 24.2R1-S2, 24.2R2, 24.4R1, and all subsequent releases.
Workaround: 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 ]
Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
References (1)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2025-30656)Record last updated .