# CVE-2019-6250: Integer overflow in n/a

> An authenticated attacker can exploit an integer overflow in ZeroMQ to overwrite memory and execute arbitrary code on the target system.

- **Severity:** High 8.8 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Jan 2019
- **Updated:** 4 Aug 2024
- **Also known as:** ALPINE-CVE-2019-6250, DEBIAN-CVE-2019-6250, DSA-4368-1, GHSA-383h-xx34-hq84, MGASA-2019-0054, SUSE-SU-2019:0110-1, UBUNTU-CVE-2019-6250, openSUSE-SU-2019:0087-1, openSUSE-SU-2024:11264-1, openSUSE-SU-2024:13821-1, openSUSE-SU-2026:11459-1

## What is CVE-2019-6250?

CVE-2019-6250 is a high-severity vulnerability in Debian Debian Linux, published on 13 Jan 2019. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A pointer overflow, with code execution, was discovered in ZeroMQ libzmq (aka 0MQ) 4.2.x and 4.3.x before 4.3.1. A v2_decoder.cpp zmq::v2_decoder_t::size_ready integer overflow allows an authenticated attacker to overwrite an arbitrary amount of bytes beyond the bounds of a buffer, which can be leveraged to run arbitrary code on the target system. The memory layout allows the attacker to inject OS commands into a data structure located immediately after the problematic buffer (i.e., it is not necessary to use a typical buffer-overflow exploitation technique that changes the flow of control).

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2019-6250?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `zeromq` | SUSE:Linux Enterprise Module for Basesystem 15 | All versions | 4.2.3-3.3.2 |
| `python-pyzmq` | openSUSE:Tumbleweed | All versions | 27.1.0-3.1 |

Products: Debian Debian Linux, Zeromq Libzmq.

## How do I fix CVE-2019-6250?

Upgrade to a fixed version.

## Is CVE-2019-6250 being exploited?

There is no known exploitation of CVE-2019-6250 in the wild and no public exploit code.

Public exploit code:

- https://github.com/AkashicYiTai/CVE-2019-6250-libzmq (github_poc): https://github.com/AkashicYiTai/CVE-2019-6250-libzmq
- End-to-end pre-auth RCE lab for CVE-2019-6250 (libzmq <= 4.3.0, ZMTP/2.0 wire-protocol) (github_poc): https://github.com/dinosn/cve-2019-6250-lab

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- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-6250 and fix it if it is affected.

What it is: CVE-2019-6250 is a high-severity vulnerability in Debian Debian Linux, published on 13 Jan 2019. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2019-6250 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2019-6250/ (Markdown: https://insights.sbomify.com/CVE-2019-6250/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-6250
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-6250
- OSV: https://osv.dev/vulnerability/CVE-2019-6250

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-6250/
Summaries are generated and may contain mistakes; the official description above is the record.