Improper input validation in Better-Auth Scim

CVE-2026-67330

@better-auth/scim (a better-auth plugin) versions >= 1.4.0-beta.27 through <= 1.6.21 and >= 1.7.0-beta.0 through <= 1.7.0-beta.9 contain an authorization bypass. SCIM token issuance did not reject provider IDs already used by existing SSO, SAML, OIDC, generic OAuth, or social account providers, and the same logical provider ID was used for both SCIM provider configuration and account ownership. An authenticated user could mint a SCIM token whose provider ID collided with an existing provider namespace, causing SCIM user routes to resolve account rows the token never provisioned. This allowed listing, reading, updating (including rewriting global profile/email fields without uniqueness checks), and deleting global user accounts and sessions, resulting in account takeover and unauthorized deprovisioning. Fixed in 1.6.22 and 1.7.0-beta.10 (1.7.0-rc.0).

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.004 (28.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-67330?
CVE-2026-67330 is a critical-severity vulnerability in Better-Auth Scim, classified under Improper Input Validation. CVSS score: 9.9/10. Published 2026-08-01.
How severe is CVE-2026-67330?
Critical severity. CVSS v3 base score is 9.9 out of 10.