CVE-2021-27279

Public Exploit

Description

MyBB before 1.8.25 allows stored XSS via nested [email] tags with MyCode (aka BBCode).

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.38%
Vendor Advisory mybb.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://mybb.com/versions/1.8.25/ release notes vendor advisory
https://github.com/mybb/mybb/security/advisories/GHSA-6483-hcpp-p75w third party advisory exploit
https://github.com/mybb/mybb/commit/cb781b49116bf5c4d8deca3e17498122b701677a third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-27279?
CVE-2021-27279 has been scored as a medium severity vulnerability.
How to fix CVE-2021-27279?
To fix CVE-2021-27279, 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-2021-27279 being actively exploited in the wild?
It is possible that CVE-2021-27279 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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