Is CVE-2026-123798 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-123798 being exploited in the wild.

How severe is CVE-2026-123798?

High severity, with a CVSS score of 8.1, published 9 November 2026.

Which products and versions are affected?

Supertokens Core 11.3.0 to 11.3.6, 11.4.0 to 11.4.6, 12.0.0 to 12.0.9.

Is there a fix for CVE-2026-123798?

Yes: fixed in 11.3.7, 11.4.7, 12.0.10. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-123798 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-123798?

Check whether you run Supertokens Core at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-123798: SuperTokens Core XML signature wrapping in SAML verification

CVE-2026-123798 · Severity: high · CVSS 8.1 · Published 2026-11-09

SuperTokens Core is an open-source authentication server that supports SAML login. A flaw in SAML signature validation allows an attacker to forge authentication by moving genuinely signed XML elements within a SAML response, then injecting attacker-controlled identity data. An ordinary user of any configured identity provider can exploit this to impersonate other users without valid credentials.

Technologies: Supertokens Core. Vendors: Supertokens.

Quick answers

Is CVE-2026-123798 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-123798 being exploited in the wild.
How severe is CVE-2026-123798?: High severity, with a CVSS score of 8.1, published 9 November 2026.
Which products and versions are affected?: Supertokens Core 11.3.0 to 11.3.6, 11.4.0 to 11.4.6, 12.0.0 to 12.0.9.
Is there a fix for CVE-2026-123798?: Yes: fixed in 11.3.7, 11.4.7, 12.0.10. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-123798 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-123798?: Check whether you run Supertokens Core at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: 11.3.7, 11.4.7, 12.0.10

Technical details

The vulnerability is an XML Signature Wrapping attack in the SAML.verifySamlResponseSignature method. The code validates SAML responses using OpenSAML's SignatureValidator without first applying SAMLSignatureProfileValidator, allowing a signature to be rebound to a different XML element. Both response-level and assertion-level signing are affected, and the vulnerability is reachable through SP-initiated login even with allowIDPInitiatedLogin disabled.

Affected products

SuperTokens Core 11.3.0 to 11.3.6, 11.4.0 to 11.4.6, 12.0.0 to 12.0.9

Timeline

2026-11-09: disclosed

References

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