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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-47245 Detail

Description

MyBB is free and open source forum software. Prior to 1.8.40, the User CP Buddy/Ignore List component does not validate reciprocal buddy-list updates correctly. The usercp.php?action=do_editlists delete handler removes the selected entry from the acting user's list and then updates mybb_users.buddylist for the target account. The reciprocal update searches for the deleted target UID instead of the acting user's UID and uses the unchecked array_search() return value as an array key. A false result can be converted to index 0, removing the target account's first stored buddy while leaving the actual reciprocal entry unchanged. The uniquely identifying implementation details include false converted to index 0. This issue is fixed in version 1.8.40.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/mybb/mybb/commit/0557718f27503034fb1c2768729a2fb8239bba65 GitHub, Inc.
https://github.com/mybb/mybb/releases/tag/mybb_1840 GitHub, Inc.
https://github.com/mybb/mybb/security/advisories/GHSA-w8gm-j57p-jqpc GitHub, Inc.
https://mybb.com/versions/1.8.40 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-252 Unchecked Return Value GitHub, Inc.  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-47245
NVD Published Date:
08/18/2026
NVD Last Modified:
08/18/2026
Source:
GitHub, Inc.