# CVE-2019-6250: libzmq5: A pointer overflow, with code execution, was discovered in ZeroMQ libzmq (aka 0MQ) 4.2.x and 4.3.x before 4.3.1

CVE-2019-6250 is fixed in libzmq5 on 1 platform by libzmq5 4.2.5-1ubuntu0.1 (version 4.2.5-1ubuntu0.1), released January 13, 2019. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2019-6250
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0970
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 13, 2019

## 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).

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libzmq5 Ubuntu 18.04.6 LTS (bionic) | 4.2.5-1ubuntu0.1 | [libzmq5 4.2.5-1ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libzmq5-4.2.5-1ubuntu0.1.md) | Jan 13, 2019 |

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