| Name | CVE-2021-20236 |
| Description | A flaw was found in the ZeroMQ server in versions before 4.3.3. This flaw allows a malicious client to cause a stack buffer overflow on the server by sending crafted topic subscription requests and then unsubscribing. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| zeromq3 (PTS) | buster, buster (security) | 4.3.1-4+deb10u2 | vulnerable |
| bullseye | 4.3.4-1+deb11u1 | fixed |
| bookworm | 4.3.4-6 | fixed |
| sid, trixie | 4.3.5-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| zeromq3 | source | (unstable) | 4.3.3-1 | | | |
Notes
[buster] - zeromq3 <no-dsa> (Minor issue)
[stretch] - zeromq3 <ignored> (Minor issue, too intrusive to backport)
https://github.com/zeromq/libzmq/pull/3959
https://github.com/zeromq/libzmq/security/advisories/GHSA-qq65-x72m-9wr8
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=22488