{"id":"CVE-2026-54774","aliases":["GHSA-rpj7-hr7h-w6p9"],"url":"https://o3.security/vulnerability/CVE-2026-54774","summary":"CoreWCF: SamlSerializer skips SignatureValue verification when SAML signing token is not an X.509 certificate","details":"### Impact\nWhen a service is configured to validate SAML tokens using a method other than X.509 certificate signing, the final signature verification is skipped.\n\n#### Preconditions\nThe service is configured to authenticate using SAML tokens and an out of band token resolver (commonly the IssuerTokenResolver of IssuedTokenServiceCredential) holds a non-X.509 SecurityToken whose key identifier the attacker can reference in the assertion’s `<KeyInfo>` - for example a `BinarySecretSecurityToken` representing the symmetric proof key issued by a WS-Trust symmetric-key holder-of-key STS.\n\n### Patches\nFixed in CoreWCF v1.8.1 and v1.9.1\n\n### Workarounds\nNone","published":"2026-07-08T22:17:07.314Z","modified":"2026-08-12T03:51:18.238658645Z","cvss":{"score":7.4,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"},"epss":{"score":0.00203,"percentile":0.10483,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"NuGet","name":"CoreWCF.Primitives","fixedVersion":"1.8.1"},{"ecosystem":"NuGet","name":"CoreWCF.Primitives","fixedVersion":"1.9.1"}],"fix":{"url":"https://github.com/CoreWCF/CoreWCF/commit/65d09022749854ba943e376aefb958dec05b00d8","label":"CoreWCF/CoreWCF@65d0902"},"references":[{"type":"WEB","url":"https://github.com/CoreWCF/CoreWCF/releases/tag/v1.8.1"},{"type":"WEB","url":"https://github.com/CoreWCF/CoreWCF/releases/tag/v1.9.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54774.json"},{"type":"ADVISORY","url":"https://github.com/CoreWCF/CoreWCF/security/advisories/GHSA-rpj7-hr7h-w6p9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54774"},{"type":"FIX","url":"https://github.com/CoreWCF/CoreWCF/commit/65d09022749854ba943e376aefb958dec05b00d8"},{"type":"FIX","url":"https://github.com/CoreWCF/CoreWCF/commit/b914495ce63c44924664643b60a262e7595081a4"},{"type":"FIX","url":"https://github.com/CoreWCF/CoreWCF/commit/e7454132876ecc7e2cf80e541a44376eeb54979b"},{"type":"PACKAGE","url":"https://github.com/CoreWCF/CoreWCF"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:18.238658645Z"}}