# CVE-2016-1256: Denial of service in n/a

> Remote attackers can cause a denial of service in Juniper Junos OS by sending malformed IGMPv3 packets, affecting network availability.

- **Severity:** Medium 5.3 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Jan 2016
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-pxg8-6jj2-8w2g

## What is CVE-2016-1256?

CVE-2016-1256 is a medium-severity denial of service vulnerability in Juniper Junos, published on 15 Jan 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Juniper Junos OS before 12.1X44-D55, 12.1X46 before 12.1X46-D40, 12.1X47 before 12.1X47-D25, 12.3 before 12.3R10, 12.3X48 before 12.3X48-D20, 13.2 before 13.2R8, 13.2X51 before 13.2X51-D40, 13.3 before 13.3R7, 14.1 before 14.1R5, 14.1X53 before 14.1X53-D18 or 14.1X53-D30, 14.1X55 before 14.1X55-D25, 14.2 before 14.2R4, 15.1 before 15.1R2, and 15.1X49 before 15.1X49-D10 allow remote attackers to cause a denial of service via a malformed IGMPv3 packet, aka a "multicast denial of service."

Weakness: CWE-399

## Which versions are affected by CVE-2016-1256?

It affects 1 product.


Products: Juniper Junos.

## How do I fix CVE-2016-1256?

No fix has been published for CVE-2016-1256 yet. Limit exposure of the affected software until one is available.

## Is CVE-2016-1256 being exploited?

There is no known exploitation of CVE-2016-1256 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-2016-1256 and fix it if it is affected.

What it is: CVE-2016-1256 is a medium-severity denial of service vulnerability in Juniper Junos, published on 15 Jan 2016. 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-2016-1256 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-2016-1256/ (Markdown: https://insights.sbomify.com/CVE-2016-1256/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-1256
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-1256
- OSV: https://osv.dev/vulnerability/CVE-2016-1256

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-1256/
Summaries are generated and may contain mistakes; the official description above is the record.