Every CVE Search/ Get API key

CVE-2020-36400

ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability...

9.8 Critical

ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability than CVE-2021-20235.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
High
Integrity
High
Availability
High

Exploit likelihood

1.84%Up 1.0 points since Jul 1, 2021
90%50%10%1%

What each source reports

NVD Score used 9.8

ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability than CVE-2021-20235.

Record
CVE-2020-36400
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0
7.5 HighAV:N/AC:L/Au:N/C:P/I:P/A:P
Weakness
CWE-787
Updated
2026-11-02
CVE List No score

ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability than CVE-2021-20235.

Record
CVE-2020-36400
Updated
2026-11-02
EUVDEUVD-2020-23928 No score

ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability than CVE-2021-20235.

Record
EUVD-2020-23928
Updated
2026-11-03
GitHub AdvisoriesGHSA-fw28-qj4f-2jpx No score

ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability...

ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability than CVE-2021-20235.

Record
GHSA-fw28-qj4f-2jpx
Weakness
CWE-787
Updated
2026-11-02
OSV 9.8

ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability than CVE-2021-20235.

Record
CVE-2020-36400
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-02

Affected products

History

History
RecordedChangedSources
aliasesEUVD
first indexedCVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2020-36400 is a critical vulnerability (CVSS 9.8) in Zeromq Libzmq, published July 1, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.84%, the 79th percentile. No source names a fixed version.

References

MoveEnter Open