CVE-2026-47245

MyBB: Buddy list corruption

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.

We have discovered 1,463 live websites that are affected by CVE-2026-47245.

Run a Free Instant Scan



Affected Software

Product  MyBB
Category Message Boards
Vulnerable Domains1,463 live websites (100% of MyBB install base)
Vulnerable Versions
  • from 0 through 1.8.40
Vulnerable Versions Count21 versions ( 100% of all versions)


Common Weakness Enumeration

CWE-252 Unchecked Return Value



Details

  • Published - Aug 18, 2026
  • Updated - Aug 18, 2026

Website Distribution by Country

Number of websites using CVE-2026-47245
United States552 websites


Germany377 websites
Poland130 websites
France76 websites
GB37 websites
Turkey25 websites
Netherlands23 websites
Italy22 websites
Iran18 websites
Russia18 websites

Website Distribution by TLD

Number of websites using CVE-2026-47245
.com535 websites
.de268 websites
.net152 websites
.org91 websites
.pl87 websites
.eu32 websites
.ru23 websites
.it18 websites
.info13 websites
.fr13 websites

Vulnerable Versions

Vulnerable versions are highlighted in red

Websites affected by CVE-2026-47245

Top websites that are affected by CVE-2026-47245. Please click on the "Contact us" link to get more information.
DomainCountryRankContacts
*********.****.com United States**,***
******.******.org United States**,***
*****.****.tv United States***,***
********.pl Poland***,***
*************.org Laos***,***
*************.net United States***,***
************.pl Poland***,***
********.net United States***,***
**********.org United States***,***
*******.com United States***,***
See full domain list

FAQ

CVE-2026-47245 is Unchecked Return Value in MyBB
A total of 1,463 websites have been identified as vulnerable to CVE-2026-47245, based on global website indexing conducted by WebTechSurvey.
The MyBB is affected by the CVE-2026-47245 vulnerability.
MyBB versions up to 1.8.40 are vulnerable to CVE-2026-47245.
CVE-2026-47245 is resolved in version 1.8.40 of MyBB.