CVE-2026-82753
Description
Allocation of Resources Without Limits or Throttling vulnerability in ash-project ash_authentication_oauth2_server allows an unauthenticated attacker to exhaust database storage and memory. The /authorize endpoint is unauthenticated by design. With Client ID Metadata Documents enabled, resolve_client/3 in AshAuthentication.Oauth2Server.CIMD fetches the document for each new URL-shaped client_id and upserts a client row, with no cap on the number of rows, no expiry or garbage collection, and no length bound on the fetched fields; the document was also placed in CIMD.Cache before validation, so even rejected documents held cache memory until their TTL. An attacker serving valid documents at many distinct URLs creates one permanent client row per URL, each able to carry multi-megabyte strings, growing storage and memory without bound. This issue affects ash_authentication_oauth2_server: from 0.3.0 before 0.3.1.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
Package impact
| Ecosystem | Package | Vulnerable | Fixed |
|---|---|---|---|
| Hex | ash_authentication_oauth2_server | >=0.3.0,<0.3.1 | 0.3.1 |
References
- https://github.com/ash-project/ash_authentication_oauth2_server/security/advisories/GHSA-9pv3-wxjm-f846
- https://cna.erlef.org/cves/CVE-2026-82753.html
- https://github.com/ash-project/ash_authentication_oauth2_server/commit/45e24f69e0f95d67413e2508acc2264156acb5ac
- https://hex.pm/packages/ash_authentication_oauth2_server
- https://osv.dev/vulnerability/EEF-CVE-2026-82753
CWEs
CWE-770
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.