CVE-2026-71848: Hono: Algorithmic Complexity DoS in Language Middleware

August 7, 2026

The languageDetector middleware is vulnerable to algorithmic complexity denial of service when processing a crafted language tag containing a large number of hyphen-separated subtags.

References

github.com/advisories/GHSA-54fx-42gc-7vw4
github.com/honojs/hono/commit/f70e2c31684387b3231cc38512a31df6ca76a1c7
github.com/honojs/hono/releases/tag/v4.12.34
github.com/honojs/hono/security/advisories/GHSA-54fx-42gc-7vw4
nvd.nist.gov/vuln/detail/CVE-2026-71848

Code Behaviors & Features

Detect and mitigate CVE-2026-71848 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Dependency Scanning using SBOM also detects vulnerabilities from proprietary advisories that this site does not include. Learn more about Dependency Scanning using SBOM →