LiveHelperChat has department-level authorization bypass in holdaction, blockuser, and transferchat endpoints
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-27954
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 8 Nov 2026, 01:05 UTC · Revision 1
Source evidence
LiveHelperChat has department-level authorization bypass in holdaction, blockuser, and transferchat endpoints
core-osv · Original sourcePublished 26 Feb 2026, 01:42 UTC
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.
osv:CVE-2026-27954
Complete source record
{
"id": "ae8dc9831525a8fd01182a3f726fcb777490ba57733711941a2e134e05d65197",
"url": "https://osv.dev/vulnerability/CVE-2026-27954",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "LiveHelperChat has department-level authorization bypass in holdaction, blockuser, and transferchat endpoints",
"summary": "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.",
"evidence": "osv:CVE-2026-27954",
"products": [],
"severity": "medium",
"structured": {
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"aliases": [
"CVE-2026-27954",
"GHSA-87wc-2p86-h3w7"
],
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{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U"
}
],
"affected": [
{
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{
"repo": "https://github.com/livehelperchat/livehelperchat",
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"strategy": "StringRangeExpression"
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{
"cpe": "cpe:2.3:a:livehelperchat:live_helper_chat:*:*:*:*:*:*:*:*",
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"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-27954.json"
}
}
],
"modified": "2026-10-28T02:30:52.595892016Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27954.json",
"https://github.com/LiveHelperChat/livehelperchat/security/advisories/GHSA-87wc-2p86-h3w7",
"https://nvd.nist.gov/vuln/detail/CVE-2026-27954"
],
"provider_metadata": {
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],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27954.json"
}
},
"related_cves": [
{
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"evidence": "/id"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 521189,
"published_at": "2026-02-26T01:42:38.225+00:00"
}