CVE-2021-27890

Public Exploit

Description

SQL Injection vulnerablity in MyBB before 1.8.26 via theme properties included in theme XML files.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 5.71% Top 15%
Third-Party Advisory packetstormsecurity.com Third-Party Advisory sonarsource.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/mybb/mybb/security/advisories/GHSA-r34m-ccm8-mfhq release notes third party advisory patch
http://packetstormsecurity.com/files/161908/MyBB-1.8.25-Remote-Command-Execution.html vdb entry third party advisory
https://blog.sonarsource.com/mybb-remote-code-execution-chain third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-27890?
CVE-2021-27890 has been scored as a high severity vulnerability.
How to fix CVE-2021-27890?
To fix CVE-2021-27890, 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-2021-27890 being actively exploited in the wild?
It is possible that CVE-2021-27890 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~6% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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