CVE-2018-1000503

Severity: medium (CVSS 4.3 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-06-26 · updated 2026-06-17
Weakness: CWE-269

Description

MyBB Group MyBB contains a Incorrect Access Control vulnerability in Private forums that can result in Users can view posts from private forums without having the password. This attack appear to be exploitable via Subscribe to a forum through IDOR. This vulnerability appears to have been fixed in 1.8.15.

Affected products

mybb: before 1.8.15 — fixed in 1.8.15

How to fix

Upgrade to a fixed version: mybb 1.8.15. Check the vendor advisory for mitigations.

References

http://www.batterystapl.es/2018/03/local-file-inclusion-and-reading.html
https://blog.mybb.com/2018/03/15/mybb-1-8-15-released-security-maintenance-release/
http://www.batterystapl.es/2018/03/local-file-inclusion-and-reading.html
https://blog.mybb.com/2018/03/15/mybb-1-8-15-released-security-maintenance-release/

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