Medium severity · published Aug 18, 2026
CVE-2026-73502
kin-openapi openapi3filter: unauthenticated nil-pointer panic when validating a request against a `content` parameter whose media type has no schema
5.3
CVSS
0.5%
EPSS
No
On KEV
Description
kin-openapi is a Go project for handling OpenAPI files. From 0.2.0 until 0.144.0, openapi3filter.ValidateRequest can encounter a NULL-pointer-dereference denial of service when an operation declares a content parameter whose application/json media type has no schema. In openapi3filter/req_resp_decoder.go, the default defaultContentParameterDecoder dereferences mt.Schema.Value without checking whether mt.Schema is nil, even though doc.Validate() accepts the document under OpenAPI 3.0.x and 3.1.x. A single unauthenticated request supplying the parameter value can panic request validation, causing an aborted request with log growth in the common synchronous net/http path or a full process crash in integrations without recovery. This issue is fixed in version 0.144.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 43% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KI
kin-openapi · getkin
>= 0.2.0, < 0.144.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-73502
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-73502
github.com
https://github.com/getkin/kin-openapi/commit/68ac2affa325514d7d6e731204d6a1edf6bdff64
github.com
https://github.com/getkin/kin-openapi/releases/tag/v0.144.0
github.com
https://github.com/getkin/kin-openapi/security/advisories/GHSA-jpcw-4wr7-c3vq
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