CSRF in Honojs @Hono/oauth-Providers

CVE-2026-81888

@hono/oauth-providers is Authentication middleware for Hono. Prior to version 0.8.6, the built-in social login providers accept an OAuth callback even when the `state` value is absent on both sides, so the anti-CSRF check passes for a callback that never came from a genuine login attempt. This defeats the `state`-based CSRF protection under default usage. Version 0.8.6 has a patch.

Vulnerability class: CSRF (Cross-Site Request Forgery)

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-81888?
CVE-2026-81888 is a medium-severity vulnerability in Honojs @Hono/oauth-Providers, classified under Cross-Site Request Forgery (CSRF). CVSS score: 5.4/10. Published 2026-08-31.
How severe is CVE-2026-81888?
Medium severity. CVSS v3 base score is 5.4 out of 10.