CVE-2015-8973

Severity: high (CVSS 8.3 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% 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-284

Description

xmlhttp.php in MyBB (aka MyBulletinBoard) before 1.6.18 and 1.8.x before 1.8.6 and MyBB Merge System before 1.8.6 allows remote attackers to bypass intended access restrictions via vectors related to the forum password.

Affected products

mybb Merge System: through 1.8.5
mybb: through 1.6.17; 1.8.0, 1.8.1, 1.8.2, 1.8.3, 1.8.4, 1.8.5

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/94397
https://blog.mybb.com/2015/09/07/mybb-1-8-6-1-6-18-merge-system-1-8-6-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/94397
https://blog.mybb.com/2015/09/07/mybb-1-8-6-1-6-18-merge-system-1-8-6-release/

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