CVE-2021-39338

Summary

The MyBB Cross-Poster WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and sanitization via several parameters found in the ~/classes/MyBBXPSettings.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 1.0. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.

Affected Software

Weaknesses

• CWE-79: CWE-79 Cross-site Scripting (XSS)

ADP Enrichment

CVE Program Container

Additional References

• https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39338
• https://github.com/BigTiger2020/word-press/blob/main/MyBB%20Cross-Poster.md
• https://plugins.trac.wordpress.org/browser/mybb-cross-poster/trunk/classes/MyBBXPSettings.php

CISA ADP Vulnrichment

• SSVC:
• Exploitation: none
  • Automatable: no
  • Technical Impact: partial

References

• https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39338
• https://github.com/BigTiger2020/word-press/blob/main/MyBB%20Cross-Poster.md
• https://plugins.trac.wordpress.org/browser/mybb-cross-poster/trunk/classes/MyBBXPSettings.php

• ←Previous
• Next→