CVE-2026-100350 kin-openapi deepObject query decoding repeatedly compiles an invariant regular expression
An unauthenticated attacker can cause excessive resource consumption in kin-openapi by sending requests with many query keys, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-100350?
CVE-2026-100350 is a medium-severity denial of service vulnerability in getkin kin-openapi, published on 15 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-100350?
2 open source packages ship an affected version, including github.com/getkin/kin-openapi.
| Package | Affected | Fixed in |
|---|---|---|
github.com/getkin/kin-openapi Go | From 0.145.0 | 0.146.0 |
github.com/getkin/kin-openapi Go | From 0.145.0 | 0.146.0 |
How do I fix CVE-2026-100350?
Upgrade github.com/getkin/kin-openapi to 0.146.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-100350 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-100350 exists.
Sources
Also known as GHSA-h4r5-mxv5-8mjc, UBUNTU-CVE-2026-100350.