CVE-2026-45121

Published: Ago 18, 2026 Last Modified: Ago 18, 2026

ExploitDB:

Other exploit source:

Google Dorks:

MEDIUM 4,3

Source: [email protected]

Attack Vector: network

Attack Complexity: low

Privileges Required: low

User Interaction: none

Scope: unchanged

Confidentiality: low

Integrity: none

Availability: none

Description

AI Translation Available

MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not check permissions consistently when listing calendars, allowing authenticated users to access titles of calendars that are otherwise inaccessible. The affected calendar-selection paths in calendar.php perform permission checks against an invalid calendar context before returning calendar titles. The uniquely identifying implementation details include titles of inaccessible calendars, and invalid calendar permission context. This issue is fixed in version 1.8.40.

863

Incorrect Authorization

Incomplete

Abstraction: Class Structure: Simple

Common Consequences

Security Scopes Affected:

Confidentiality Integrity Access Control Availability

Potential Impacts:

Read Application Data Read Files Or Directories Modify Application Data Modify Files Or Directories Gain Privileges Or Assume Identity Bypass Protection Mechanism Execute Unauthorized Code Or Commands Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Dos: Resource Consumption (Other)