Description
kin-openapi is a Go project for handling OpenAPI files. From 0.136.0 until 0.143.0, openapi3filter accepts OpenAPI 3.1 array schemas without an items keyword and then dereferences the nil Schema.Items value while decoding application/x-www-form-urlencoded or multipart/form-data request bodies, response headers, and other array parameter surfaces. A remote unauthenticated client can reach an affected operation with a nonempty request or matching response and deterministically trigger a nil-pointer panic during ValidateRequest or ValidateResponse. OpenAPI 3.0 documents are not affected because document validation rejects arrays without items, and JSON request bodies use a different decoder path. This issue is fixed in version 0.143.0.
References4
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 50 · as of 10 November 2026
- CWE
- CWE-248CWE-476
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