CVE-2021-39338

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.

CVSS v3 5.5 MEDIUM
CVSS v2.0 2.1 LOW

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

2.1^/10

CVSS v2.0 : LOW

Vector : AV:N/AC:H/Au:S/C:N/I:P/A:N

Exploitability : 3.9 / Impact : 2.9

Access Vector NETWORK

Access Complexity HIGH

Authentication SINGLE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

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

Configurations

Configuration 1 (hide)

cpe:2.3:a:mybb_cross-poster_project:mybb_cross-poster:*:*:*:*:*:wordpress:*:*

History

No history.

Information

Published : 2021-10-15 13:15

Updated : 2024-11-21 06:19

NVD link : CVE-2021-39338

Mitre link : CVE-2021-39338

CVE.ORG link : CVE-2021-39338

JSON object : View

Products Affected

mybb_cross-poster_project

mybb_cross-poster

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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