CVE-2026-67330

better-auth SCIM 1.4.0-beta.27 through 1.6.21 Account Takeover via Provider-ID Collision

State
Published
Severity
9.4 Critical
Published
Aug 1, 2026
Updated
Oct 8, 2026
Reserved
Jul 29, 2026

Read the record on cve.org

Description

@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).

Scores

CVSSScoreVectorSource
4.09.4 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:HVulnCheck
3.19.9 CriticalCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HVulnCheck

Weaknesses

  • CWE-20 Improper Input Validation

Affected Products

ProductVersions
scimbetter-auth
  • 1.4.0-beta.27 and laterAffected
scimbetter-auth
  • 1.7.0-beta.0 and laterAffected

References

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.