Vulnerability 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 algorithm specified in the JWT header to influence signature verification when the selected JWK did not explicitly define an algorithm. This could enable JWT algorithm confusion and, in certain configurations, allow forged tokens to be accepted. The JWK/JWKS JWT verification middleware has been updated to require an explicit allowlist of asymmetric algorithms when verifying tokens. The middleware no longer derives the verification algorithm from untrusted JWT header values. This vulnerability is fixed in 4.11.4.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Hono | Hono | < 4.11.4 |
Related Weaknesses (CWE)
References
- https://github.com/honojs/hono/commit/190f6e28e2ca85ce3d1f2f54db1310f5f3eab134Patch
- https://github.com/honojs/hono/security/advisories/GHSA-3vhc-576x-3qv4Third Party Advisory
FAQ
What is CVE-2026-22818?
CVE-2026-22818 is a vulnerability with a CVSS score of 8.2 (HIGH). 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 algorithm specified in...
How severe is CVE-2026-22818?
CVE-2026-22818 has been rated HIGH with a CVSS base score of 8.2/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-22818?
Check the references section above for vendor advisories and patch information. Affected products include: Hono Hono.