CVE-2026-44457 Hono: Cache Middleware ignores Vary: Authorization / Vary: Cookie leading to cross-user cache leakage
The Hono framework's cache middleware may serve cached responses to different users, leaking sensitive data across sessions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-44457?
CVE-2026-44457 is a medium-severity vulnerability in honojs hono, published on 13 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.18, Cache Middleware does not skip caching for responses that declare per-user variance via Vary: Authorization or Vary: Cookie. As a result, a response cached for one authenticated user may be served to subsequent requests from different users. This vulnerability is fixed in 4.12.18.
Weakness: CWE-524
Which versions are affected by CVE-2026-44457?
2 open source packages ship an affected version, including hono. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
hono npm | All versions | 4.12.18 |
hono npm | All versions | 4.12.18 |
Products include Hono Hono.
How do I fix CVE-2026-44457?
Upgrade hono to 4.12.18 or later.
Is CVE-2026-44457 being exploited?
There is no known exploitation of CVE-2026-44457 in the wild and no public exploit code.
Other vulnerabilities in honojs hono
- CVE-2026-27700 Hono is Vulnerable to Authentication Bypass by IP Spoofing in AWS Lambda ALB conninfo
- CVE-2026-22817 JWT Algorithm Confusion via Unsafe Default (HS256) in Hono JWT Middleware Allows Token Forgery and Auth Bypass
- CVE-2026-22818 JWT algorithm confusion in Hono JWK Auth Middleware when JWK lacks "alg" (untrusted header.alg fallback)
- CVE-2025-62610 Hono Improperly Authorizes JWT Audience Validation
- CVE-2026-29045 Hono: Arbitrary file access via serveStatic vulnerability
Sources
Also known as CLEANSTART-2026-DH65511, CLEANSTART-2026-PL20463, ECHO-40a5-8a54-e3c7, GHSA-p77w-8qqv-26rm, MINI-3gcj-w842-2vwp, MINI-3mgf-26wj-5gmw and 8 more.