CVE-2026-27954
LiveHelperChat has department-level authorization bypass in holdaction, blockuser, and transferchat endpoints
No known exploitation. EPSS puts it in the 31st percentile. Only a workaround so far.
What to do
No fixed build is published yet. The vendor describes a workaround.
- LivehelperchatAffected: <= 4.52Upgrade to: not statedStated by: CVE record
- Livehelperchat Live Helper ChatAffected: ≤ 4.52Upgrade to: after 4.52Stated by: NVD
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.4% chance of exploitation activity in the next 30 days, which ranks it in the 31st percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 2 days, from the signal feeds we watch.
- Workaround availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Scored 6.5 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
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