CVE-2020-15166

Denial of Service in ZeroMQ

Description

In ZeroMQ before version 4.3.3, there is a denial-of-service vulnerability. Users with TCP transport public endpoints, even with CURVE/ZAP enabled, are impacted. If a raw TCP socket is opened and connected to an endpoint that is fully configured with CURVE/ZAP, legitimate clients will not be able to exchange any message. Handshakes complete successfully, and messages are delivered to the library, but the server application never receives them. This is patched in version 4.3.3.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.97% Top 25%
Vendor Advisory gentoo.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org
Affected: zeromq libzmq
Published at:
Updated at:

References

Link Tags
https://github.com/zeromq/libzmq/security/advisories/GHSA-25wp-cf8g-938m third party advisory patch
https://github.com/zeromq/libzmq/pull/3913 third party advisory patch
https://github.com/zeromq/libzmq/pull/3973 third party advisory patch
https://security.gentoo.org/glsa/202009-12 third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BZ5IMNQXDB52JFBXHFLK4AHVORFELNNG/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YFW2ZELCCPS4VLU4OSJOH5YL6KFKTFYW/ vendor advisory
https://lists.debian.org/debian-lts-announce/2020/11/msg00017.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2020-15166?
CVE-2020-15166 has been scored as a high severity vulnerability.
How to fix CVE-2020-15166?
To fix CVE-2020-15166, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-15166 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-15166 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-15166?
CVE-2020-15166 affects zeromq libzmq.
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