CVE-2026-123798highCWE-287CWE-347

CVE-2026-123798: high-severity vulnerability in supertokens-core

SuperTokens Core: SAML XML Signature Wrapping authentication bypass — any IdP user can authenticate as any other user

Published

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.1epss 0.2%
SuperTokens Core is an open source authentication server. From 11.3.0 until 11.3.7, 11.4.7, and 12.0.10, SAML.verifySamlResponseSignature calls OpenSAML SignatureValidator.validate without first applying SAMLSignatureProfileValidator. The Core can therefore accept a cryptographically valid signature that references a different XML element from the Response or Assertion whose NameID and attributes are used for authentication. An ordinary user of the configured identity provider can move a genuinely signed element elsewhere in the document while supplying an attacker-authored identity-bearing element, causing XML Signature Wrapping authentication as another IdP user. Both response-level and assertion-level signing paths are affected, and SP-initiated login remains reachable without enabling allowIDPInitiatedLogin. This issue is fixed in versions 11.3.7, 11.4.7, and 12.0.10.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N