CVE-2021-21431

Name: CVE-2021-21431
Creator: NVD / NIST
Published: 2021-04-09T16:15:11.837+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.1/10EPSS 1.07%

Last modified Jun 17, 2026

CVE-2021-21431 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. sopel-channelmgnt is a channelmgnt plugin for sopel. In versions prior to 2.0.1, on some IRC servers, restrictions around the removal of the bot using the kick/kickban command could be bypassed when kicking multiple users at once. EPSS estimates a 1.07% chance of exploitation in the next 30 days.

Description

sopel-channelmgnt is a channelmgnt plugin for sopel. In versions prior to 2.0.1, on some IRC servers, restrictions around the removal of the bot using the kick/kickban command could be bypassed when kicking multiple users at once. We also believe it may have been possible to remove users from other channels but due to the wonder that is IRC and following RfCs, We have no POC for that. Freenode is not affected. This is fixed in version 2.0.1. As a workaround, do not use this plugin on networks where TARGMAX > 1.

Metrics

CVSS 3.1

8.1/10

CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:N/I:H/A:H

EPSS Probability

1.07%

60.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Mirahezebots	Channelmgnt	< 2.0.1

References

https://github.com/MirahezeBots/sopel-channelmgnt/commit/7c96d400358221e59135f0a0be0744f3fad73856Patch, Third Party Advisory
https://github.com/MirahezeBots/sopel-channelmgnt/security/advisories/GHSA-23c7-6444-399mThird Party Advisory
https://pypi.org/project/sopel-plugins.channelmgnt/Product, Third Party Advisory
https://github.com/MirahezeBots/sopel-channelmgnt/commit/7c96d400358221e59135f0a0be0744f3fad73856Patch, Third Party Advisory
https://github.com/MirahezeBots/sopel-channelmgnt/security/advisories/GHSA-23c7-6444-399mThird Party Advisory
https://pypi.org/project/sopel-plugins.channelmgnt/Product, Third Party Advisory

Timeline

Published: Apr 9, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-21431?

How severe is CVE-2021-21431?

CVE-2021-21431 has a CVSS score of 8.1/10 (HIGH severity). The EPSS model estimates a 1.07% probability of exploitation in the next 30 days.

How do I fix CVE-2021-21431?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-21431?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST