Description
kin-openapi is a Go project for handling OpenAPI files. From 0.145.0 until 0.146.0, openapi3filter repeatedly calls regexp.MustCompile for the same parameter-name regular expression inside the per-query-key loop in urlValuesDecoder.DecodeObject used to decode a deepObject query parameter. An unauthenticated remote client can send an affected endpoint a request containing many unrelated query keys, causing ValidateRequest to perform work and allocations proportional to the attacker-controlled key count for every deepObject parameter. The expression itself is fixed and this is not regular expression denial of service; the resource consumption comes from loop-invariant recompilation. This issue is fixed in version 0.146.0.
References4
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 40 · as of 10 November 2026
- CWE
- CWE-400CWE-770CWE-1050
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