# CVE-2026-123800: SuperTokens Core: App-scoped API key can overwrite the parent connection URI domain's credentials and take over sibling applications

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

SuperTokens Core is an open source authentication server. From 6.0.0 until 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, and 12.3.1, Multitenancy.checkPermissionsForCreateOrUpdate in src/main/java/io/supertokens/multitenancy/Multitenancy.java does not adequately authorize updates to a parent connection URI domain or the base tenant. In a licensed multi-tenant deployment with multiple applications under one non-default connection URI domain and separate api_keys, an attacker holding one application's valid API key can update the parent domain because the CUD-target branch checks the domain without requiring the source application and tenant to be public. Because api_keys is not protected, the attacker can replace the parent key and then sibling application keys, read or modify sibling users, obtain sessions as those users, establish persistence through a sibling dashboard user, and lock out the sibling application's own key. In the advisory's v2 create or update handlers, omitting the optional identifier produces a base-tenant target that skips the permission branches and enterprise-feature gate, allowing changes to firstFactors, required secondary factors, and recipe-enabled flags that affect login integrity and availability. The base-target variant still rejects coreConfig and does not establish key theft. This issue is fixed in versions 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, and 12.3.1.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- supertokens / supertokens-core: >= 6.0.0, < 6.0.24 (affected); >= 7.0.0, < 7.0.23 (affected); >= 8.0.0, < 8.0.7 (affected); >= 9.0.0, < 9.0.6 (affected); >= 9.1.0, < 9.1.6 (affected); >= 9.2.0, < 9.2.7 (affected); >= 9.3.0, < 9.3.5 (affected); >= 10.0.0, < 10.0.8 (affected); >= 10.1.0, < 10.1.9 (affected); >= 11.0.0, < 11.0.9 (affected); >= 11.1.0, < 11.1.4 (affected); >= 11.2.0, < 11.2.4 (affected); >= 11.3.0, < 11.3.8 (affected); >= 11.4.0, < 11.4.8 (affected); >= 12.0.0, < 12.0.11 (affected); >= 12.1.0, < 12.1.2 (affected); >= 12.2.0, < 12.2.1 (affected); >= 12.3.0, < 12.3.1 (affected). Source: CNA: GitHub_M

## Severity and prioritization

- CVSS 3.1: 9.9 (critical); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H; source: CNA: GitHub_M

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-639, CWE-863

## 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-4rf2-xqvf-8rcx (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/supertokens/supertokens-core/commit/13c3de170dd40dd217db0f6bd2bded0948476a42 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/1cc02b971f064c2fa2d9bc74b9e85795fdc6a7e5 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/1d9dcb03ce0691d9b8abee48f86cc2729a6008cb (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/337bb3eba812a5ee52d57854701820a0580b6050 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/4902b713f31306ca41148070d10b6185f0e85201 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/4d1ef0e177681f4f74995e4a25a17d224effe115 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/61bfd3ebde1cf4b092da85ee884fa15e288aad51 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/64dfa92c50a2ec288fe787ee5c2fad45548a6475 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/8db9b0c39f97f240e116821434d4eb3c907faccf (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/8e48ef856becbaaeb50ad4c915be1d7ce279416b (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/9b0d3a9fdbdcb48dd7dd9d520075bbefbae3cf9b (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/a186f1013c784de8a796a732e925e1870fec0f40 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/b58bc3d03549d20495df71c03ef5478799c184db (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/bf6184f027a99bd1b3b1df3d20e376dda6521399 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/c6d7dc7d73b9bb3075b3f7a1a0c0c5780430c292 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/df79f3b4399ef31aea4cb44cc7b65761a2cb94a7 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/e616f4002c31d256f9ff6cb3d3685b924ef53a6d (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/commit/ff9ca3ec53861a91996c4e9581fa6f2e01331736 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v10.0.8 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v10.1.9 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v11.0.9 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v11.1.4 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v11.2.4 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v11.3.8 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v11.4.8 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v12.0.11 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v12.1.2 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v12.2.1 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v12.3.1 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v6.0.24 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v7.0.23 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v8.0.7 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v9.0.6 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v9.1.6 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v9.2.7 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/supertokens/supertokens-core/releases/tag/v9.3.5 (CNA: GitHub_M; x_refsource_MISC)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2026-123800; retrieved 2026-11-09; source updated 2026-11-09

Revision: ac5974971cca33b7fda06923572c58229f1f0b6b3177d10550a3d824d3305cf1

Canonical: https://y2.dev/cve/CVE-2026-123800

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