Medium severity · published May 13, 2026
CVE-2026-44457
Hono: Cache Middleware ignores Vary: Authorization / Vary: Cookie leading to cross-user cache leakage
5.3
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HO
hono · honojs
< 4.12.18 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-44457
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-44457
Vendor Advisory
https://github.com/honojs/hono/security/advisories/GHSA-p77w-8qqv-26rm
More from hono
9.8
CVE-2026-29045
Hono: Arbitrary file access via serveStatic vulnerability
8.1
CVE-2025-62610
Hono Improperly Authorizes JWT Audience Validation
7.5
CVE-2026-39408
Hono has a path traversal in toSSG() allows writing files outside the output directory
7.5
CVE-2026-27700
Hono is Vulnerable to Authentication Bypass by IP Spoofing in AWS Lambda ALB conninfo
7.5
CVE-2025-58362
Hono contains a flaw in URL path parsing, potentially leading to path confusion