CVE-2026-47366 in phpBB
Summary
by MITRE • 06/12/2026
Improper verification of access permissions when modifying permissions through the Administration Control Panel (ACP) allowed an authenticated administrator to grant permissions beyond the level authorized for their account, resulting in privilege escalation within the administrative interface.
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Analysis
by VulDB Data Team • 06/12/2026
This vulnerability represents a critical access control flaw that undermines the security posture of administrative interfaces by allowing unauthorized privilege escalation through improper permission verification mechanisms. The issue occurs within the Administration Control Panel where authenticated administrators can manipulate access controls to grant themselves elevated privileges beyond their authorized scope. This weakness stems from insufficient validation of permission modifications, creating a path for malicious or compromised administrative accounts to expand their access rights without proper authorization checks. The vulnerability directly relates to cwe-284 which defines improper access control as a fundamental security weakness where systems fail to properly enforce access restrictions. From an operational perspective this flaw enables attackers to escalate privileges within the administrative interface, potentially gaining access to sensitive system functions, user data, or critical infrastructure controls. The impact extends beyond simple permission manipulation as it can lead to complete system compromise when combined with other vulnerabilities or when the compromised administrator account has access to sensitive administrative functions. Attackers can leverage this vulnerability to bypass normal security controls and establish persistent access to privileged system resources, making it particularly dangerous in environments where administrative accounts have broad system access. The flaw demonstrates a failure in the principle of least privilege enforcement, where the system does not properly validate that administrative actions remain within the scope of authorized permissions. This vulnerability aligns with attack techniques documented in the attack pattern taxonomy under privilege escalation methods, specifically targeting the modification of access control permissions as a means to gain elevated system privileges. Organizations implementing administrative interfaces must ensure that all permission modifications are strictly validated against the originating account's authorization levels, implementing proper access control enforcement mechanisms that prevent users from granting themselves permissions beyond their established privileges. The remediation approach should focus on implementing robust input validation, enforcing strict authorization checks, and maintaining audit trails of all permission modifications to detect and prevent unauthorized access control changes. Security controls should include mandatory authorization verification for all administrative actions, implementation of role-based access controls with proper segregation of duties, and regular monitoring of administrative activities for suspicious permission modification patterns that could indicate exploitation attempts.