Skip to main content
Public proof of conceptFix available

CVE-2019-6250

A public proof of concept exists; no exploitation attested.

  • Published2019-01-13
  • Fixed in4.3.1
  • WeaknessCWE-190

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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).

Timeline

dates in UTC
  1. 2019-01-1315:29CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-11-02 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2019-6250?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2019-6250?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Zeromq libzmq
BranchAffectedFixed in
4.3≥ 4.3.0, < 4.3.14.3.1
4.2≥ 4.2.0, ≤ 4.2.5no fix published
Debian debian linux
BranchAffectedFixed in
9.0= 9.0no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • python-pyzmqopenSUSE:Tumbleweedall versions · fixed in 27.1.0-3.1
  • zeromqSUSE:Linux Enterprise Module for Basesystem 15all versions · fixed in 4.2.3-3.3.2
  • zeromqopenSUSE:Tumbleweedall versions · fixed in 4.3.4-2.2
  • zeromqMageia:6all versions · fixed in 4.2.2-1.1.mga6
  • zeromqCleanStartall versions · fixed in 4.3.1-r0
  • zeromqAlpine:v3.24all versions · fixed in 4.3.1-r0
  • zeromqAlpine:v3.23all versions · fixed in 4.3.1-r0
  • zeromqAlpine:v3.22all versions · fixed in 4.3.1-r0

21 more package ranges on OSV.dev

Vendor advisories

  • CVE-2019-6250 Red Hat Product Security

    zeromq: Integer overflow in zmq::v2_decoder_t::size_ready

Full record on NVD

Fix

  1. Update Zeromq libzmq to 4.3.1

Advisories and patches

Detection

read 2026-11-02 22:42 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
2 repositories, unverifiedAkashicYiTai/CVE-2019-6250-libzmqdinosn/cve-2019-6250-lab
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

  • NVDCVSS 3.08.8read 2026-10-23
  • NVDCVSS 2.09read 2026-10-23
  • NVDweakness (CWE)CWE-190read 2026-10-23
  • FIRST EPSSEPSS score9.7 %2026-11-02
  • PoC-in-GitHubproof of concept2read 2026-11-02
  • OSVaffected packages—

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Published
2019-01-13
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2019-6250?

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).

Is CVE-2019-6250 actively exploited?

Active exploitation of CVE-2019-6250 has not been confirmed. Its EPSS score was 9.7% on 2026-11-02, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2019-6250?

CVE-2019-6250 has a CVSS v3 base score of 8.8 (HIGH severity), with vector string CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Running zeromq? Hear about its next vulnerability

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, October 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database

Sources for this record