High 7.1Published Mar 19, 2026

CVE-2026-27953ormar has a Pydantic Validation Bypass via Kwargs Injection in Model Constructor

Updated under an hour ago (Oct 27, 2026, 5:23 PM ET)

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Every CVE for ormar-orm ormar

Exploited in the last 30 days

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.

CVSS: 7.1 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
Weakness (CWE): CWE-915, CWE-20
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Mar 20, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

ormar-orm ormar ormar_orm:ormar (from the name)	before 0.23.1	CNA record
collerek ormar collerek:ormar	before 0.23.1	NVD

References

References

https://github.com/ormar-orm/ormar/security/advisories/GHSA-f964-whrq-44h8	x-refsource-confirm, exploit, mitigation, vendor-advisory
https://github.com/ormar-orm/ormar/commit/7f22aa21a7614b993970345b392dabb0ccde0ab3	x-refsource-misc, patch
https://github.com/ormar-orm/ormar/blob/master/examples/fastapi_quick_start.py#L55	x-refsource-misc, patch
https://github.com/ormar-orm/ormar/blob/master/ormar/fields/foreign_key.py#L41	x-refsource-misc, patch
https://github.com/ormar-orm/ormar/blob/master/ormar/models/helpers/pydantic.py#L108	x-refsource-misc, patch
https://github.com/ormar-orm/ormar/blob/master/ormar/models/model.py#L89	x-refsource-misc, patch
https://github.com/ormar-orm/ormar/blob/master/ormar/models/newbasemodel.py#L128	x-refsource-misc, patch
https://github.com/ormar-orm/ormar/blob/master/ormar/models/newbasemodel.py#L292	x-refsource-misc, patch
https://github.com/ormar-orm/ormar/releases/tag/0.23.1	x-refsource-misc, product, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.