cvedb.io
CVE-2026-69207
MEDIUM · CVSS 5.3
EPSS exploitation probability: 0%
Published 2026-08-07T21:17:29.847 · Last modified 2026-08-07T21:17:29.847

Summary

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.34, the built-in CORS middleware, hono/cors, is vulnerable to a regular expression denial of service (ReDoS). During a preflight OPTIONS request, the middleware parses the attacker-controlled Access-Control-Request-Headers header using a whitespace-tolerant regular expression whose backtracking makes its running time quadratic in the input length. Because the header value is bounded only by the deployment's maximum HTTP header size, a single preflight carrying a long run of whitespace can consume seconds of CPU and block request processing. On runtimes that share one execution thread across requests, this stalls concurrent requests as well, and repeated requests can render the service unresp

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.