CVE-2021-32921

Description

An issue was discovered in Prosody before 0.11.9. It does not use a constant-time algorithm for comparing certain secret strings when running under Lua 5.2 or later. This can potentially be used in a timing attack to reveal the contents of secret strings to an attacker.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 3.22% Top 15%
Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory prosody.im
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://blog.prosody.im/prosody-0.11.9-released/ release notes vendor advisory
http://www.openwall.com/lists/oss-security/2021/05/13/1 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2021/05/14/2 mailing list mitigation third party advisory
https://www.debian.org/security/2021/dsa-4916 third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6MFFBZWXKPZEVZNQSVJNCUE7WRF3T7DG/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LWJ2DG2DFJOEFEWOUN26IMYYWGSA2ZEE/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GUN63AHEWB2WRROJHU3BVJRWLONCT2B7/ vendor advisory
https://security.gentoo.org/glsa/202105-15 third party advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00016.html third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2021/06/msg00018.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-32921?
CVE-2021-32921 has been scored as a medium severity vulnerability.
How to fix CVE-2021-32921?
To fix CVE-2021-32921, 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-2021-32921 being actively exploited in the wild?
It is possible that CVE-2021-32921 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~3% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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