better-auth SCIM 1.4.0-beta.27 through 1.6.21 Account Takeover via Provider-ID Collision
Summary
| CVE | CVE-2026-67330 |
|---|---|
| State | PUBLISHED |
| Assigner | VulnCheck |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-01 13:17:03 UTC |
| Updated | 2026-08-01 13:17:03 UTC |
| 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). |
Risk And Classification
Primary CVSS: v4.0 9.4 CRITICAL from [email protected]
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Problem Types: CWE-20 | CWE-20 Improper Input Validation
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 9.4 | CRITICAL | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/C... |
| 4.0 | CNA | CVSS | 9.4 | CRITICAL | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
| 3.1 | [email protected] | Primary | 9.9 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| 3.1 | CNA | CVSS | 9.9 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
LowUser Interaction
NoneConfidentiality
HighIntegrity
HighAvailability
HighSub Conf.
HighSub Integrity
HighSub Availability
HighCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
ChangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Better-auth | Scim | affected 1.4.0-beta.27 * semver | Not specified |
| CNA | Better-auth | Scim | affected 1.7.0-beta.0 * semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.vulncheck.com/advisories/better-auth-scim-beta-27-through-account-takeover-... | [email protected] | www.vulncheck.com | |
| github.com/better-auth/better-auth/security/advisories/GHSA-rjg6-39jm-rgg4 | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.