CoreWCF NetNamedPipe transport accepts attach to a pre-existing named pipe instance
CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1, CoreWCF NetNamedPipe transport accepts attachment to a pre-existing named pipe instance, allowing local interception of NetNamedPipe traffic when an attacker races NamedPipeListener startup between shared memory GUID publication and service named pipe creation. This issue is fixed in versions 1.8.1 and 1.9.1.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-54777
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 2 Nov 2026, 17:21 UTC · Revision 1
Source evidence
CoreWCF NetNamedPipe transport accepts attach to a pre-existing named pipe instance
core-osv · Original sourcePublished 8 Jul 2026, 22:01 UTC
CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1, CoreWCF NetNamedPipe transport accepts attachment to a pre-existing named pipe instance, allowing local interception of NetNamedPipe traffic when an attacker races NamedPipeListener startup between shared memory GUID publication and service named pipe creation. This issue is fixed in versions 1.8.1 and 1.9.1.
osv:CVE-2026-54777
Complete source record
{
"id": "513faf3a26f5b0c67dff9f7fb46fc881a6ce24fd74909f842c63204863ed09e6",
"url": "https://osv.dev/vulnerability/CVE-2026-54777",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CoreWCF NetNamedPipe transport accepts attach to a pre-existing named pipe instance",
"summary": "CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1, CoreWCF NetNamedPipe transport accepts attachment to a pre-existing named pipe instance, allowing local interception of NetNamedPipe traffic when an attacker races NamedPipeListener startup between shared memory GUID publication and service named pipe creation. This issue is fixed in versions 1.8.1 and 1.9.1.",
"evidence": "osv:CVE-2026-54777",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-54777",
"aliases": [
"CVE-2026-54777",
"GHSA-6jj2-4q5c-x8g6"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/corewcf/corewcf",
"type": "GIT",
"events": [
{
"introduced": "39b2f02978e497955a560c72b5ccdff5c0dbcda1"
},
{
"fixed": "1f7a0811da5128db40fd7b868ae0aac0c581f91f"
},
{
"introduced": "0"
},
{
"fixed": "7c0920fe16adc497efae82881ac0f1e4d7ac98d0"
},
{
"fixed": "8ed9c780c7c6fb22fa215c5771dee0c1e49596b7"
},
{
"fixed": "e7d225394fd429900dcbc445dcdd53b94e964077"
}
],
"database_specific": {
"extracted_events": [
{
"range": [
{
"introduced": "1.9.0"
},
{
"fixed": "1.9.1"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"introduced": "0"
},
{
"fixed": "1.8.1"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "8ed9c780c7c6fb22fa215c5771dee0c1e49596b7"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "e7d225394fd429900dcbc445dcdd53b94e964077"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "7c0920fe16adc497efae82881ac0f1e4d7ac98d0"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v1.8.1"
},
{
"range": [
{
"fixed": "1f7a0811da5128db40fd7b868ae0aac0c581f91f"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v1.9.1"
}
]
}
}
],
"versions": [
"v1.8.0",
"v1.9.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54777.json"
}
}
],
"modified": "2026-10-28T02:30:21.375906714Z",
"provider": "osv",
"references": [
"https://github.com/CoreWCF/CoreWCF/releases/tag/v1.8.1",
"https://github.com/CoreWCF/CoreWCF/releases/tag/v1.9.1",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54777.json",
"https://github.com/CoreWCF/CoreWCF/security/advisories/GHSA-6jj2-4q5c-x8g6",
"https://nvd.nist.gov/vuln/detail/CVE-2026-54777",
"https://github.com/CoreWCF/CoreWCF/commit/8ed9c780c7c6fb22fa215c5771dee0c1e49596b7",
"https://github.com/CoreWCF/CoreWCF/commit/e7d225394fd429900dcbc445dcdd53b94e964077"
],
"provider_metadata": {
"cwe_ids": [
"CWE-367",
"CWE-665"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54777.json"
}
},
"related_cves": [
{
"value": "CVE-2026-54777",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 487704,
"published_at": "2026-07-08T22:01:21.323+00:00"
}