CVE-2026-54776CWE-306

CoreWCF: Unix Domain Socket PosixIdentity transport accepts connections that skip the security upgrade

Medium · published July 8, 2026

CVSS v3.1
4.4
EPSS
0%
Percentile
4.0
In the wild
Unconfirmed
What it is

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, a CoreWCF service hosted on Unix Domain Sockets with PosixIdentity client credentials can accept connections that skip the application/unixposix stream upgrade before dispatching messages, bypassing framing-layer identity checks in UnixPosixIdentitySecurityUpgradeProvider. This issue is fixed in versions 1.8.1 and 1.9.1.

The record
Technical detail
CVSS v3.1
4.4 · MEDIUM
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00152 · 4.0th percentile
Weakness
CWE-306 · Missing Authentication for Critical Function
Published
2026-07-08T22:04Z
EPSS history
Timeline
  • 08 JUL 22:04Z
    CoreWCF: Unix Domain Socket PosixIdentity transport accepts connections that skip the security upgrade
    cvelistv5