CVE-2016-9421

Severity: medium (CVSS 6.1 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2017-01-31 · updated 2026-06-17
Weakness: CWE-79

Description

Cross-site scripting (XSS) vulnerability in the Users module in the Admin control panel in MyBB (aka MyBulletinBoard) before 1.8.8 and MyBB Merge System before 1.8.8 might allow remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Affected products

mybb Merge System: through 1.8.7
mybb: through 1.8.7

References

http://www.openwall.com/lists/oss-security/2016/11/10/8
http://www.openwall.com/lists/oss-security/2016/11/18/1
http://www.securityfocus.com/bid/94396
https://blog.mybb.com/2016/10/17/mybb-1-8-8-merge-system-1-8-8-release/
http://www.openwall.com/lists/oss-security/2016/11/10/8
http://www.openwall.com/lists/oss-security/2016/11/18/1
http://www.securityfocus.com/bid/94396
https://blog.mybb.com/2016/10/17/mybb-1-8-8-merge-system-1-8-8-release/

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