# 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.

- **Severity:** High 8.7 (`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`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Apr 2025
- **Updated:** 10 Apr 2025
- **Also known as:** GHSA-w8cw-wx3m-wghj

## 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 (Improper Handling of Additional Special Element)

## Which versions are affected by CVE-2025-30656?

It affects 1 product.


Products: 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.

## 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](https://insights.sbomify.com/CVE-2023-36845/): Juniper Junos OS EX Series and SRX Series PHP External Variable Modification (critical 9.8, exploited in the wild)
- [CVE-2020-1631](https://insights.sbomify.com/CVE-2020-1631/): Juniper Junos OS Path Traversal (high 8.8, exploited in the wild)
- [CVE-2025-21590](https://insights.sbomify.com/CVE-2025-21590/): Juniper Junos OS Improper Isolation or Compartmentalization (medium 6.7, exploited in the wild)
- [CVE-2023-36851](https://insights.sbomify.com/CVE-2023-36851/): Juniper Junos OS SRX Series Missing Authentication for Critical Function (medium 5.3, exploited in the wild)
- [CVE-2023-36844](https://insights.sbomify.com/CVE-2023-36844/): Juniper Junos OS EX Series PHP External Variable Modification (medium 5.3, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-30656 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2025-30656 in the wild and no public exploit code.

Affected product: Juniper Junos. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-30656/ (Markdown: https://insights.sbomify.com/CVE-2025-30656/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-30656
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-30656
- OSV: https://osv.dev/vulnerability/CVE-2025-30656

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-30656/
Summaries are generated and may contain mistakes; the official description above is the record.