Review reviewCritical

CVE-2026-67330

better-auth scim

@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 allowe...

CVSS
9.4
EPSS
-
- percentile
CISA KEV
Not listed
Published
2026.08.01
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability-
Technical severityCVSS 9.4

Vulnerability overview

@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 allowe...

Affected product and versions

Product
better-auth scim
Affected versions
>= 1.4.0-beta.27, >= 1.7.0-beta.0
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that better-auth scim and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
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
CWE
CWE-20