Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Critical severity, with a CVSS score of 9.9, published 24 July 2026.

Which products and versions are affected?

Better-Auth SCIM Plugin >= 1.4.0-beta.27, = 1.7.0-beta.0, <= 1.7.0-beta.9.

Is there a fix for This vulnerability?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is This vulnerability attacked?

It is attacked over the network, in a software library.

Check whether you run Better-Auth SCIM Plugin at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Better Auth @better-auth/scim account takeover via provider-id collision

Q: Is there a fix for This vulnerability?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

Q: How is This vulnerability attacked?

It is attacked over the network, in a software library.

Q: Am I affected?

Check whether you run Better-Auth SCIM Plugin at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Severity: critical · CVSS 9.9 · Published 2026-07-24

A vulnerability in the Better Auth SCIM plugin allows authenticated users to gain unauthorized control over other user accounts. By creating a specially crafted token, an attacker can modify profile information, change email addresses, or even delete user accounts belonging to other login providers like Google or GitHub. Additionally, a separate bug prevents the system from properly deactivating users when requested by an identity provider, potentially leaving access active for terminated employees.

Technologies: Better-Auth SCIM Plugin. Vendors: Better-Auth.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: Critical severity, with a CVSS score of 9.9, published 24 July 2026.
Which products and versions are affected?: Better-Auth SCIM Plugin >= 1.4.0-beta.27, <= 1.6.21; >= 1.7.0-beta.0, <= 1.7.0-beta.9.
Is there a fix for This vulnerability?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is This vulnerability attacked?: It is attacked over the network, in a software library.
Am I affected?: Check whether you run Better-Auth SCIM Plugin at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The @better-auth/scim plugin fails to validate that a SCIM provider ID does not collide with existing account provider namespaces (e.g., SSO, OIDC, SAML). An authenticated user can mint a SCIM token with a colliding ID, allowing the SCIM middleware to resolve and manage account rows it does not own. This enables unauthorized listing, modification, and deletion of users via SCIM endpoints. Furthermore, the plugin failed to model the 'active' attribute, causing deactivation requests to be ignored, and lacked email uniqueness checks during PUT/PATCH operations, which could lead to account hijacking or data corruption. Fixes are available in versions 1.6.22 and 1.7.0-beta.10.

Affected products

Better Auth @better-auth/scim >= 1.4.0-beta.27, <= 1.6.21; >= 1.7.0-beta.0, <= 1.7.0-beta.9

Timeline

2026-06-26: disclosed
2026-07-24: advisory

References

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