CVE-2026-54773CWE-347

CoreWCF: WS-Security signature substitution via document-wide Signature lookup

Medium · published July 8, 2026

CVSS v3.1
5.9
EPSS
0%
Percentile
29.7
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, CoreWCF WS-Security signature verification performs a document-wide ds:Signature lookup, allowing an unauthenticated remote attacker to place a SOAP header before wsse:Security and cause WSSecurityOneDotZeroReceiveSecurityHeader to verify an attacker-supplied signature instead of the security header signature. This issue is fixed in versions 1.8.1 and 1.9.1.

The record
Technical detail
CVSS v3.1
5.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00370 · 29.7th percentile
Weakness
CWE-347 · Improper Verification of Cryptographic Signature
Published
2026-07-08T22:09Z
EPSS history
Timeline
  • 08 JUL 22:09Z
    CoreWCF: WS-Security signature substitution via document-wide Signature lookup
    cvelistv5