CVE-2021-43847

Name: CVE-2021-43847
Creator: NVD / NIST
Published: 2021-12-20T22:15:08.003+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 1.18%

Last modified Jun 17, 2026

CVE-2021-43847 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. HumHub is an open-source social network kit written in PHP. Prior to HumHub version 1.10.3 or 1.9.3, it could be possible for registered users to become unauthorized members of private Spaces. EPSS estimates a 1.18% chance of exploitation in the next 30 days.

Description

HumHub is an open-source social network kit written in PHP. Prior to HumHub version 1.10.3 or 1.9.3, it could be possible for registered users to become unauthorized members of private Spaces. Versions 1.10.3 and 1.9.3 contain a patch for this issue.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

1.18%

63.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Humhub	Humhub	< 1.9.3
Humhub	Humhub	>= 1.10.0, < 1.10.3

References

https://github.com/humhub/humhub/pull/5473Patch, Third Party Advisory
https://github.com/humhub/humhub/releases/tag/v1.10.3Release Notes, Third Party Advisory
https://github.com/humhub/humhub/releases/tag/v1.9.3Release Notes, Third Party Advisory
https://github.com/humhub/humhub/security/advisories/GHSA-f5hc-5wfr-7v74Exploit, Third Party Advisory
https://huntr.dev/bounties/943dad83-f0ed-4c74-ba81-7dfce7ca0ef2/Exploit, Issue Tracking, Patch, Third Party Advisory
https://github.com/humhub/humhub/pull/5473Patch, Third Party Advisory
https://github.com/humhub/humhub/releases/tag/v1.10.3Release Notes, Third Party Advisory
https://github.com/humhub/humhub/releases/tag/v1.9.3Release Notes, Third Party Advisory
https://github.com/humhub/humhub/security/advisories/GHSA-f5hc-5wfr-7v74Exploit, Third Party Advisory
https://huntr.dev/bounties/943dad83-f0ed-4c74-ba81-7dfce7ca0ef2/Exploit, Issue Tracking, Patch, Third Party Advisory

Timeline

Published: Dec 20, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-43847?

How severe is CVE-2021-43847?

CVE-2021-43847 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 1.18% probability of exploitation in the next 30 days.

How do I fix CVE-2021-43847?

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-2021-43847?

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

Scan your code now

Source: NVD / NIST