CVE-2026-54780
CoreWCF: WS-Security Reference DigestMethod Algorithm-Suite Bypass
Description
### Impact CoreWCF’s WS-Security 1.0 receive pipeline validates the `SignatureMethod` of an incoming `ds:SignedInfo` against the configured `SecurityAlgorithmSuite`, but does not validate the `DigestMethod` declared on each `ds:Reference`. As a result, a sender can populate `ds:SignedInfo` with `SignatureMethod` values the suite accepts (for example rsa-sha256 under Basic256Sha256) while declaring a per-reference `DigestMethod` the suite rejects (for example http://www.w3.org/2000/09/xmldsig#sha1). The signature is then verified where it permits SHA-1 digests, and the message is accepted. ### Patches Fixed in CoreWCF v1.8.1 and v1.9.1 ### Workarounds None
How to fix CVE-2026-54780
To remediate CVE-2026-54780, upgrade the affected package to a fixed version below.
- —upgrade to 1.8.1 or later
Is CVE-2026-54780 being exploited?
No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-54780.
Affected packages (1)
- from 0, < 1.8.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | LOW3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N |