CVEvulnerability
CVE-2026-27953
9.8 CRITICAL
Official page ↗
- Status
- Analyzed
- Published
- 2026-03-19
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.1 HIGH — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
- CVSS 3.1 ([email protected])
- 9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-20, CWE-915
Description
ormar is a async mini ORM for Python. Versions 0.23.0 and below are vulnerable to Pydantic validation bypass through the model constructor, allowing any unauthenticated user to skip all field validation by injecting "__pk_only__": true into a JSON request body. By injecting "__pk_only__": true into a JSON request body, an unauthenticated attacker can skip all field validation and persist unvalidated data directly to the database. A secondary __excluded__ parameter injection uses the same pattern to selectively nullify arbitrary model fields (e.g., email or role) during construction. This affects ormar's canonical FastAPI integration pattern recommended in its official documentation, enabling privilege escalation, data integrity violations, and business logic bypass in any application using ormar.Model directly as a request body parameter. This issue has been fixed in version 0.23.1.
Affected configurations
• collerek ormar (< 0.23.1)
Related
References
- https://github.com/ormar-orm/ormar/blob/master/examples/fastapi_quick_start.py#L55 Patch
- https://github.com/ormar-orm/ormar/blob/master/ormar/fields/foreign_key.py#L41 Patch
- https://github.com/ormar-orm/ormar/blob/master/ormar/models/helpers/pydantic.py#L108 Patch
- https://github.com/ormar-orm/ormar/blob/master/ormar/models/model.py#L89 Patch
- https://github.com/ormar-orm/ormar/blob/master/ormar/models/newbasemodel.py#L128 Patch
- https://github.com/ormar-orm/ormar/blob/master/ormar/models/newbasemodel.py#L292 Patch
- https://github.com/ormar-orm/ormar/commit/7f22aa21a7614b993970345b392dabb0ccde0ab3 Patch
- https://github.com/ormar-orm/ormar/releases/tag/0.23.1 Product, Release Notes
- https://github.com/ormar-orm/ormar/security/advisories/GHSA-f964-whrq-44h8 Exploit, Mitigation, Vendor Advisory
- https://github.com/ormar-orm/ormar/security/advisories/GHSA-f964-whrq-44h8 Exploit, Mitigation, Vendor Advisory