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
An unauthenticated attacker can cause a sustained Denial of Service on Juniper MX and SRX devices by sending specially crafted SIP INVITE messages that trigger memory corruption in the SIP ALG.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-30656?
CVE-2025-30656 is a high-severity memory corruption vulnerability in Juniper Junos, published on 9 Apr 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-167
Which versions are affected by CVE-2025-30656?
It affects 1 product.
Products include Juniper Junos.
How do I fix CVE-2025-30656?
No fix has been published for CVE-2025-30656 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2025-30656 being exploited?
There is no known exploitation of CVE-2025-30656 in the wild and no public exploit code.
Other vulnerabilities in Juniper Junos
- CVE-2023-36845 Juniper Junos OS EX Series and SRX Series PHP External Variable Modification
- CVE-2020-1631 Juniper Junos OS Path Traversal
- CVE-2025-21590 Juniper Junos OS Improper Isolation or Compartmentalization
- CVE-2023-36851 Juniper Junos OS SRX Series Missing Authentication for Critical Function
- CVE-2023-36844 Juniper Junos OS EX Series PHP External Variable Modification
Sources
Also known as GHSA-w8cw-wx3m-wghj.