Is CVE-2026-123800 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-123800 being exploited in the wild.

How severe is CVE-2026-123800?

Critical severity, with a CVSS score of 9.9, published 9 November 2026.

Which products and versions are affected?

Supertokens Core 6.0.0 to 6.0.23, 7.0.0 to 7.0.22, 8.0.0 to 8.0.6, 9.0.0 to 9.0.5, 9.1.0 to 9.1.5, 9.2.0 to 9.2.6, 9.3.0 to 9.3.4, 10.0.0 to 10.0.7, 10.1.0 to 10.1.8, 11.0.0 to 11.0.8, 11.1.0 to 11.1.3, 11.2.0 to 11.2.3, 11.3.0 to 11.3.7, 11.4.0 to 11.4.7, 12.0.0 to 12.0.10, 12.1.0 to 12.1.1, 12.2.0, 12.3.0.

Is there a fix for CVE-2026-123800?

Yes: fixed in 6.0.24, 7.0.23, 8.0.7, 9.0.6, 9.1.6, 9.2.7, 9.3.5, 10.0.8, 10.1.9, 11.0.9, 11.1.4, 11.2.4, 11.3.8, 11.4.8, 12.0.11, 12.1.2, 12.2.1, 12.3.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-123800 attacked?

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

Am I affected by CVE-2026-123800?

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-2026-123800: SuperTokens Core authorization bypass in multitenancy connection URI updates

CVE-2026-123800 · Severity: critical · CVSS 9.9 · Published 2026-11-09

SuperTokens Core is an open-source authentication server used to manage user logins and sessions across applications. In multi-tenant deployments, an attacker with a valid API key for one application can exploit an authorization flaw to modify parent domain settings and API keys, allowing them to access other applications' user data, hijack sessions, and lock legitimate administrators out of their accounts.

Technologies: Supertokens Core. Vendors: Supertokens.

Quick answers

Is CVE-2026-123800 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-123800 being exploited in the wild.
How severe is CVE-2026-123800?: Critical severity, with a CVSS score of 9.9, published 9 November 2026.
Which products and versions are affected?: Supertokens Core 6.0.0 to 6.0.23, 7.0.0 to 7.0.22, 8.0.0 to 8.0.6, 9.0.0 to 9.0.5, 9.1.0 to 9.1.5, 9.2.0 to 9.2.6, 9.3.0 to 9.3.4, 10.0.0 to 10.0.7, 10.1.0 to 10.1.8, 11.0.0 to 11.0.8, 11.1.0 to 11.1.3, 11.2.0 to 11.2.3, 11.3.0 to 11.3.7, 11.4.0 to 11.4.7, 12.0.0 to 12.0.10, 12.1.0 to 12.1.1, 12.2.0, 12.3.0.
Is there a fix for CVE-2026-123800?: Yes: fixed in 6.0.24, 7.0.23, 8.0.7, 9.0.6, 9.1.6, 9.2.7, 9.3.5, 10.0.8, 10.1.9, 11.0.9, 11.1.4, 11.2.4, 11.3.8, 11.4.8, 12.0.11, 12.1.2, 12.2.1, 12.3.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-123800 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-123800?: 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: 6.0.24, 7.0.23, 8.0.7, 9.0.6, 9.1.6, 9.2.7, 9.3.5, 10.0.8, 10.1.9, 11.0.9, 11.1.4, 11.2.4, 11.3.8, 11.4.8, 12.0.11, 12.1.2, 12.2.1, 12.3.1

Technical details

The vulnerability exists in the Multitenancy.checkPermissionsForCreateOrUpdate method, which fails to properly authorize updates to parent connection URI domains and base tenant configurations. An attacker with one application's API key can bypass permission checks to update parent domain credentials and sibling application keys in multi-tenant deployments. Additionally, omitting an optional identifier in v2 handlers allows modification of authentication factors and recipe-enabled flags that affect login security, bypassing the enterprise-feature gate.

Affected products

SuperTokens Core 6.0.0 to 6.0.23, 7.0.0 to 7.0.22, 8.0.0 to 8.0.6, 9.0.0 to 9.0.5, 9.1.0 to 9.1.5, 9.2.0 to 9.2.6, 9.3.0 to 9.3.4, 10.0.0 to 10.0.7, 10.1.0 to 10.1.8, 11.0.0 to 11.0.8, 11.1.0 to 11.1.3, 11.2.0 to 11.2.3, 11.3.0 to 11.3.7, 11.4.0 to 11.4.7, 12.0.0 to 12.0.10, 12.1.0 to 12.1.1, 12.2.0, 12.3.0

Timeline

2026-11-09: disclosed

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