Description
Boruta is a standalone authorization server that aims to implement OAuth 2.0 and Openid Connect up to decentralized identity specifications. Prior to version 0.10.0, BorutaIdentityWeb.UserSettingsController.update/2 atomizes every key of the user-supplied request body via String.to_atom/1 before any validation. Because String.to_atom interns atoms permanently in the BEAM atom table (default cap 1,048,576 atoms; ERL_MAX_ATOMS), any authenticated end user can send PUT /users/settings with a user[<fresh-key>]=... body containing fresh keys per request and exhaust the global VM atom table. Once the table is full, the BEAM aborts with no more index entries in atom_tab and the entire OIDC server (auth, admin, gateway apps in the umbrella) crashes. The route is protected only by require_authenticated_user and a per-IP rate limit of 10 requests/second; a logged-in end user can hit it. The keys are atomized unconditionally before the downstream Accounts.update_user/6 call, so even failing updates contribute to exhaustion. This issue has been patched in version 0.10.0.
References3
Metrics
- CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/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 - EPSS — exploit probability
- 0% percentile: 34 · as of 3 November 2026
- CWE
- CWE-400CWE-770
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.