CVE-2016-9403

9.8 criticalEPSS 2.6%

Critical (9.8) in mybb. EPSS 2.6% chance of exploitation in the next 30 days.

newreply.php in MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allows remote attackers to have unspecified impact by leveraging a missing permission check.

Severity

CVSS 3.0

9.8 critical

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

EPSS: 2.6% chance of exploitation in the next 30 days; higher than 85% of CVEs (scores of 2026-10-31)
CWE: CWE-264
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/94395
https://blog.mybb.com/2016/03/11/mybb-1-8-7-merge-system-1-8-7-release/
http://www.openwall.com/lists/oss-security/2016/11/10/8

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