CVE-2026-123804mediumCWE-362CWE-613

CVE-2026-123804: medium-severity vulnerability in supertokens-core

SuperTokens Core: A session created concurrently with account unlink survives the unlink

Published

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13Vexday Risk Score

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

ssvc Trackcvss 6.8epss 0.4%
SuperTokens Core is an open source authentication server. From 7.0.0 until 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, createNewSession can resolve a primary user before unlinkAccounts detaches a login method and then insert the session after unlink has enumerated and revoked the existing sessions. A user who controls the linked login method can exploit this race to retain a signed, database-backed, refreshable session as the former primary identity after that method is unlinked; the session persists until expiry or explicit revocation. This issue is fixed in versions 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.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
Affected products
supertokens · supertokens-core
Related CVEs — supertokens-core

In the same product, most dangerous first.

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