Ad

CVE-2026-27954

MEDIUM CVSS 4.0: 4.9 EPSS 0.03%
Updated Feb 26, 2026
PHP
Parameter Value
CVSS 4.9 (MEDIUM)
Type CWE-862 (Missing Authorization)
Vendor PHP
Public PoC No

Live Helper Chat is an open-source application that enables live support websites. In versions up to and including 4.52, three chat action endpoints (holdaction.php, blockuser.php, and transferchat.php) load chat objects by ID without calling `erLhcoreClassChat::hasAccessToRead()`, allowing operators to act on chats in departments they are not assigned to. Operators with the relevant role permissions (holduse, allowblockusers, allowtransfer) can hold, block users from, or transfer chats in departments they are not assigned to.

This is a horizontal privilege escalation within one organization. As of time of publication, no known patched versions are available.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
None
No data leak
Integrity
High
Complete data modification
Availability
None
No disruption

CVSS Vector v4.0