CVE-2026-44457: Hono Authorization / Vary: Cookie Leading Vulnerability

MODERATE
Advisory Identifier: GHSA-p77w-8qqv-26rm
CVSS 5.3
CWE-524
Published
Advisory Summary

CVE-2026-44457 is a MODERATE (CVSS 5.3) authorization / vary: cookie leading vulnerability (CWE-524: Use of Cache Containing Sensitive Information) affecting Hono libraries in the npm ecosystem. The issue involves authorization / vary: cookie leading to cross-user cache leakage. Remediation is available by upgrading affected packages to version 4.12.18.

CVE-2026-44457 at a Glance

CVE Identifier CVE-2026-44457
GHSA Identifier GHSA-p77w-8qqv-26rm
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-524: Use of Cache Containing Sensitive Information
Affected Product Hono
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-44457

To remediate this vulnerability, upgrade all affected Hono dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

hono fixed: 4.12.18
npm install hono@4.12.18
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

npm ls hono

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-44457, inspect your project dependencies using npm:

npm ls hono

Analyze the terminal output to locate any version of Hono in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.12.18), your application is affected.

Note: The npm ls hono command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-524: Use of Cache Containing Sensitive Information, where the code uses a cache that contains sensitive information, but the cache can be read by an actor outside of the intended control sphere. In Hono, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary 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. ### Details The Cache Middleware skips caching when a response carries `Vary: *`, certain `Cache-Control` directives (`private`, `no-store`, `no-cache`), or `Set-Cookie`. However, `Vary: Authorization` and `Vary: Cookie` — the standard signals defined in RFC 9110 / RFC 9111 to indicate per-user responses — are not treated as cache-skip reasons. This issue arises when applications use the Cache Middleware on endpoints that return user-specific data and rely on `Vary: Authorization` or `Vary: Cookie` to scope the response per user, without also setting `Cache-Control: private`. ### Impact A user may receive a cached response that was originally generated for a different authenticated user. This may lead to: - Disclosure of personally identifiable information or other user-specific data present in the response body - Inconsistent or incorrect behavior in user-specific endpoints This issue affects applications that use the Cache Middleware on endpoints whose responses vary by `Authorization` or `Cookie` and that do not also set `Cache-Control: private`.

CVE-2026-44457 Affected Hono Versions

1 component(s)
Fixed Versions:
4.12.18
Product / Package Ecosystem Affected Versions Fixed Version
hono
npm
< 4.12.18
4.12.18

References

Frequently Asked Questions

What is CVE-2026-44457?
CVE-2026-44457 is a security vulnerability in Hono involving Authorization / Vary: Cookie leading to cross-user cache leakage under CWE-524: Use of Cache Containing Sensitive Information.
Which Hono versions are affected?
Affected versions include releases prior to 4.12.18 across affected packages: hono.
What version fixes CVE-2026-44457?
Upgrading to 4.12.18 (or the latest patched release for your respective branch) resolves the vulnerability.
Is hono affected?
Yes, hono is affected in releases prior to 4.12.18. Upgrade your dependency to 4.12.18 or later.
What is the CVSS score of CVE-2026-44457?
CVE-2026-44457 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
What CWE is associated with CVE-2026-44457?
CVE-2026-44457 is classified under CWE-524: Use of Cache Containing Sensitive Information (The code uses a cache that contains sensitive information, but the cache can be read by an actor outside of the intended control sphere.).
How can I check npm dependencies for CVE-2026-44457?
Run the dependency tree command: 'npm ls hono'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-p77w-8qqv-26rm",
  "modified" : "2026-05-14T20:35:40Z",
  "published" : "2026-05-09T00:28:46Z",
  "aliases" : [ "CVE-2026-44457" ],
  "summary" : "Hono's Cache Middleware ignores Vary: Authorization / Vary: Cookie leading to cross-user cache leakage",
  "details" : "### Summary\n\nCache 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.\n\n### Details\n\nThe Cache Middleware skips caching when a response carries `Vary: *`, certain `Cache-Control` directives (`private`, `no-store`, `no-cache`), or `Set-Cookie`. However, `Vary: Authorization` and `Vary: Cookie` — the standard signals defined in RFC 9110 / RFC 9111 to indicate per-user responses — are not treated as cache-skip reasons.\n\nThis issue arises when applications use the Cache Middleware on endpoints that return user-specific data and rely on `Vary: Authorization` or `Vary: Cookie` to scope the response per user, without also setting `Cache-Control: private`.\n\n### Impact\n\nA user may receive a cached response that was originally generated for a different authenticated user. This may lead to:\n\n- Disclosure of personally identifiable information or other user-specific data present in the response body\n- Inconsistent or incorrect behavior in user-specific endpoints\n\nThis issue affects applications that use the Cache Middleware on endpoints whose responses vary by `Authorization` or `Cookie` and that do not also set `Cache-Control: private`.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "hono"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.12.18"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/honojs/hono/security/advisories/GHSA-p77w-8qqv-26rm"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-44457"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/honojs/hono"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-524" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-09T00:28:46Z",
    "nvd_published_at" : "2026-05-13T16:16:57Z"
  }
}