CVE-2026-45119 — MEDIUM (4.6)

Vulnerability Description

MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP UTF-8 Conversion module does not validate certain requests correctly, allowing same-site attackers to alter table encoding and deny service with a specially crafted URL. The do=all control flow in admin/modules/tools/system_health.php performs ALTER TABLE operations, column rewrite phases, and fulltext index rebuilds on GET requests for the database table named by the table parameter without request verification. The uniquely identifying implementation details include GET requests without request verification. This issue is fixed in version 1.8.40.

CVSS Score

4.6

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

REQUIRED

Scope

UNCHANGED

Confidentiality

NONE

Integrity

LOW

Availability

LOW

Related Weaknesses (CWE)

CWE-352

References

FAQ

What is CVE-2026-45119?

CVE-2026-45119 is a vulnerability with a CVSS score of 4.6 (MEDIUM). MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP UTF-8 Conversion module does not validate certain requests correctly, allowing same-site attackers to alter table encoding an...

How severe is CVE-2026-45119?

CVE-2026-45119 has been rated MEDIUM with a CVSS base score of 4.6/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-45119?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.