# CVE-2026-123798: SuperTokens Core: SAML XML Signature Wrapping authentication bypass — any IdP user can authenticate as any other user

Status: published. Published: 2026-11-09. Updated: 2026-11-09.

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.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- supertokens / supertokens-core: >= 12.0.6, < 12.0.10 (affected); >= 11.4.0, < 11.4.7 (affected); >= 11.3.0, < 11.3.7 (affected). Source: CNA: GitHub_M

## Severity and prioritization

- CVSS 3.1: 8.1 (high); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N; source: CNA: GitHub_M

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-287, CWE-347

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/supertokens/supertokens-core/security/advisories/GHSA-gvx2-mwmj-wwvj (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/supertokens/supertokens-core/commit/8d06b0cfb5409c5bf505051ddfcb94d66367caae (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/9cba541ae2ed87b878d11b257bc9b8b78341f50a (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/d0773f2a6497411aeda5d4f03d3d135a2a3ae79c (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v11.3.7 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v11.4.7 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v12.0.10 (CNA: GitHub_M; x_refsource_MISC)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2026-123798; retrieved 2026-11-09; source updated 2026-11-09

Revision: 79d9c94375905fbc2f8757d00ecce3a51c8eefd244feeb749c7b6353e50d20ed

Canonical: https://y2.dev/cve/CVE-2026-123798

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