JWT Algorithm Confusion via Unsafe Default (HS256) in Hono JWT Middleware Allows Token Forgery and Auth Bypass (honojs hono)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.17 % · percentile 6 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
Description
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.11.4, there is a flaw in Hono’s JWK/JWKS JWT verification middleware allowed the JWT header’s alg value to influence signature verification when the selected JWK did not explicitly specify an algorithm. This could enable JWT algorithm confusion and, in certain configurations, allow forged tokens to be accepted. As part of this fix, the JWT middleware now requires the alg option to be explicitly specified. This prevents algorithm confusion by ensuring that the verification algorithm is not derived from untrusted JWT header values. This vulnerability is fixed in 4.11.4.
Weaknesses (CWE)
- CWE-347 — Improper Verification of Cryptographic Signature
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N | GitHub_M |
| CVSS 3.1 | HIGH 8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N | NVD · security-advisories@github.com (Secondary) |
| CVSS 3.1 | MEDIUM 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N | NVD · nvd@nist.gov (Primary) |
Advisories
- GHSA-f67f-6cw9-8mq4 — Hono JWT Middleware's JWT Algorithm Confusion via Unsafe Default (HS256) Allows Token Forgery and Auth Bypass
European references
- ENISA EUVD · EUVD-2026-2018
- GCVE · GCVE-0-2026-22817
Affected configurations (NVD CPE)
cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:*< 4.11.4
Affected products
| Product | Versions |
|---|---|
| honojs · hono | affected < 4.11.4 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |