GHSA-6JJ2-4Q5C-X8G6
Vulnerability from github – Published: 2026-06-19 20:46 – Updated: 2026-06-19 20:46Impact
CoreWCF NetNamedPipe transport accepts attach to a pre-existing named pipe instance, allowing local interception of NetNamedPipe traffic. NetNamedPipe creates a shared memory object based on the listening url, then generated a unique GUID for the named pipe it will be using and saves this to the shared memory object. Then it creates the named pipe to listen for clients. This requires an attacker to race the service and create the named pipe between the service publishing the GUID to the shared memory location (which the attacker needs to read) and the service creating the named pipe itself.
Patches
Fixed in CoreWCF v1.8.1 and v1.9.1
Workarounds
None
{
"affected": [
{
"package": {
"ecosystem": "NuGet",
"name": "CoreWCF.NetNamedPipe"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.8.1"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "NuGet",
"name": "CoreWCF.NetNamedPipe"
},
"ranges": [
{
"events": [
{
"introduced": "1.9.0"
},
{
"fixed": "1.9.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-54777"
],
"database_specific": {
"cwe_ids": [
"CWE-367",
"CWE-665"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-19T20:46:55Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "### Impact\nCoreWCF NetNamedPipe transport accepts attach to a pre-existing named pipe instance, allowing local interception of NetNamedPipe traffic. NetNamedPipe creates a shared memory object based on the listening url, then generated a unique GUID for the named pipe it will be using and saves this to the shared memory object. Then it creates the named pipe to listen for clients. This requires an attacker to race the service and create the named pipe between the service publishing the GUID to the shared memory location (which the attacker needs to read) and the service creating the named pipe itself.\n\n### Patches\nFixed in CoreWCF v1.8.1 and v1.9.1\n\n### Workarounds\nNone",
"id": "GHSA-6jj2-4q5c-x8g6",
"modified": "2026-06-19T20:46:55Z",
"published": "2026-06-19T20:46:55Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/CoreWCF/CoreWCF/security/advisories/GHSA-6jj2-4q5c-x8g6"
},
{
"type": "PACKAGE",
"url": "https://github.com/CoreWCF/CoreWCF"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L",
"type": "CVSS_V3"
}
],
"summary": "CoreWCF NetNamedPipe transport accepts attach to a pre-existing named pipe instance"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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