### Impact A CoreWCF service hosted on Unix Domain Sockets with the PosixIdentity client credential type (UnixDomainSocketBinding with Security.Mode = TransportCredentialOnly and Security.Transport.ClientCredentialType = PosixIdentity) does not require the client to perform the application/unixposix stream upgrade before dispatching messages. ### Patches Fixed in CoreWCF v1.8.1 and v1.9.1 ### Workarounds Restrict filesystem access to the UDS socket file using owner/group/mode (e.g. chmod 0660 plus a dedicated group) so that only the POSIX users who are already authorized to invoke the service can connect at all. This makes the missing-upgrade behaviour equivalent to the operating system’s filesystem permissions instead of relying on framing-layer identity checks. Avoid relying on ServiceSecurityContext.PrimaryIdentity for authorization decisions, or back it up with an authentication-required authorization policy that rejects anonymous principals.
Update CoreWCF.UnixDomainSocket to 1.8.1; CoreWCF.UnixDomainSocket to 1.9.1 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanCoreWCF: Unix Domain Socket PosixIdentity transport accepts connections that skip the security upgrade affects CoreWCF.UnixDomainSocket (nuget), CoreWCF.UnixDomainSocket (nuget). Severity is medium. ### Impact A CoreWCF service hosted on Unix Domain Sockets with the PosixIdentity client credential type (UnixDomainSocketBinding with Security.Mode = TransportCredentialOnly and Security.Transport.ClientCredentialType = PosixIdentity) does not require the client to perform the application/unixposix stream upgrade before dispatching messages. ### Patches Fixed in CoreWCF v1.8.1 and v1.9.1 ### Workarounds Restrict filesystem access to the UDS socket file using owner/group/mode (e.g. chmod 0660 plus a dedicated group) so that only the POSIX users who are already authorized to invoke the service can connect at all. This makes the missing-upgrade behaviour equivalent to the operating system’s filesystem permissions instead of relying on framing-layer identity checks. Avoid relying on ServiceSecurityContext.PrimaryIdentity for authorization decisions, or back it up with an authentication-required authorization policy that rejects anonymous principals.
AI coding agents often install or upgrade packages automatically in nuget. A medium vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
### Impact A CoreWCF service hosted on Unix Domain Sockets with the PosixIdentity client credential type (UnixDomainSocketBinding with Security.Mode = TransportCredentialOnly and Security.Transport.ClientCredentialType = PosixIdentity) does not require the client to perform the application/unixposix stream upgrade before dispatching messages. ### Patches Fixed in CoreWCF v1.8.1 and v1.9.1 ### Workarounds Restrict filesystem access to the UDS socket file using owner/group/mode (e.g. chmod 0660 plus a dedicated group) so that only the POSIX users who are already authorized to invoke the service can connect at all. This makes the missing-upgrade behaviour equivalent to the operating system’s filesystem permissions instead of relying on framing-layer identity checks. Avoid relying on ServiceSecurityContext.PrimaryIdentity for authorization decisions, or back it up with an authentication-required authorization policy that rejects anonymous principals.
Update CoreWCF.UnixDomainSocket to 1.8.1; CoreWCF.UnixDomainSocket to 1.9.1 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanCoreWCF: Unix Domain Socket PosixIdentity transport accepts connections that skip the security upgrade affects CoreWCF.UnixDomainSocket (nuget), CoreWCF.UnixDomainSocket (nuget). Severity is medium. ### Impact A CoreWCF service hosted on Unix Domain Sockets with the PosixIdentity client credential type (UnixDomainSocketBinding with Security.Mode = TransportCredentialOnly and Security.Transport.ClientCredentialType = PosixIdentity) does not require the client to perform the application/unixposix stream upgrade before dispatching messages. ### Patches Fixed in CoreWCF v1.8.1 and v1.9.1 ### Workarounds Restrict filesystem access to the UDS socket file using owner/group/mode (e.g. chmod 0660 plus a dedicated group) so that only the POSIX users who are already authorized to invoke the service can connect at all. This makes the missing-upgrade behaviour equivalent to the operating system’s filesystem permissions instead of relying on framing-layer identity checks. Avoid relying on ServiceSecurityContext.PrimaryIdentity for authorization decisions, or back it up with an authentication-required authorization policy that rejects anonymous principals.
AI coding agents often install or upgrade packages automatically in nuget. A medium vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|
| CoreWCF.UnixDomainSocketnuget | <1.8.1 | 1.8.1 |
|---|---|---|
| CoreWCF.UnixDomainSocketnuget | >=1.9.0,<1.9.1 | 1.9.1 |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard| Package | Affected range | Fixed version |
|---|
| CoreWCF.UnixDomainSocketnuget | <1.8.1 | 1.8.1 |
|---|---|---|
| CoreWCF.UnixDomainSocketnuget | >=1.9.0,<1.9.1 | 1.9.1 |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard