Vulnerability in Corewcf

CVE-2026-54783

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 endorsing and supporting signature verification does not ensure the selected ds:Signature covers the expected Security header target, allowing an attacker with one captured signed SOAP envelope to replay arbitrary service operations as the victim principal. This issue is fixed in versions 1.8.1 and 1.9.1.

EPSS: 0.001 (4.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

  • Corewcf — versions >= 1.9.0, < 1.9.1, < 1.8.1

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-54783?
CVE-2026-54783 is a high-severity vulnerability in Corewcf, classified under Authentication Bypass by Capture-replay. CVSS score: 7.4/10. Published 2026-07-08.
How severe is CVE-2026-54783?
High severity. CVSS v3 base score is 7.4 out of 10.