CVE-2026-65635: Boruta dynamic client registration allows creation of over-privileged OAuth clients

Severity: high (CVSS 8.3 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-30 · updated 2026-10-23
Weakness: CWE-653

Description

Improper Isolation or Compartmentalization vulnerability in malach-it boruta (Elixir.Boruta.Openid module) allows attackers to register OpenID Connect clients with administrative privileges through the dynamic client registration entry point. Boruta.Openid.register_client/3 forwards caller-supplied registration parameters to the administrative client creation path without a public/admin field-level allowlist, so an unauthenticated registrant can set security-sensitive attributes including supported grant types, authorized scopes, PKCE enforcement, public refresh and revocation behavior, token lifetimes, and signing settings. The library does not distinguish between metadata a public registrant is allowed to set and administrative controls that should require operator approval. This vulnerability is associated with program files lib/boruta/openid.ex and program routines 'Elixir.Boruta.Openid':register_client/3, 'Elixir.Boruta.Openid':parse_registration_params/2. This issue affects boruta from 2.3.0 before 2.3.7.

Affected products

malach-it boruta: from 2.3.0 before 2.3.7 — fixed in 2.3.7

How to fix

Upgrade to a fixed version: malach-it boruta 2.3.7. Check the vendor advisory for mitigations.

References

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