CVE-2015-8973

8.3 highEPSS 1.6%

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.

Severity

CVSS 3.0

8.3 high

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L

EPSS: 1.6% chance of exploitation in the next 30 days; higher than 76% of CVEs (scores of 2026-10-31)
CWE: CWE-284
Published: 2017-01-31
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

mybb:merge_system
mybb:mybb

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

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