CVE-2026-29087: @hono/node server @hono/node-server Has Authorization Bypass For Vulnerability
HIGHCVE-2026-29087 is a HIGH (CVSS 7.5) @hono/node-server has authorization bypass for vulnerability (CWE-863: Incorrect Authorization) affecting @hono/node server libraries in the npm ecosystem. The issue involves @hono/node-server has authorization bypass for protected static paths via encoded slashes in serve static middleware. Remediation is available by upgrading affected packages to version 1.19.10.
CVE-2026-29087 at a Glance
Security Impact
CVSS: 7.5
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:H/I:N/A:N).
How to Fix CVE-2026-29087
To remediate this vulnerability, upgrade all affected @hono/node server dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
npm install @hono/node-server@1.19.10Run the following command in your project directory to verify that all resolved dependencies use the patched release:
npm ls @hono/node-serverHow to Check if You Are Affected
To determine whether your Node.js application is affected by CVE-2026-29087, inspect your project dependencies using npm:
npm ls @hono/node-serverAnalyze the terminal output to locate any version of @hono/node server in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.19.10), your application is affected.
Note: The npm ls @hono/node-server 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-863: Incorrect Authorization, where the product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. In @hono/node server, 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
CVE-2026-29087 Affected @hono/node server Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
@hono/node-server
|
npm |
< 1.19.10
|
1.19.10
|
References
Frequently Asked Questions
What is CVE-2026-29087?
Which @hono/node server versions are affected?
What version fixes CVE-2026-29087?
Is @hono/node-server affected?
What is the CVSS score of CVE-2026-29087?
What CWE is associated with CVE-2026-29087?
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Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-wc8c-qw6v-h7f6",
"modified" : "2026-03-06T22:43:58Z",
"published" : "2026-03-04T20:05:49Z",
"aliases" : [ "CVE-2026-29087" ],
"summary" : "@hono/node-server has authorization bypass for protected static paths via encoded slashes in Serve Static Middleware",
"details" : "## Summary\n\nWhen using @hono/node-server's static file serving together with route-based middleware protections (e.g. protecting `/admin/*`), inconsistent URL decoding can allow protected static resources to be accessed without authorization.\n\nIn particular, paths containing encoded slashes (`%2F`) may be evaluated differently by routing/middleware matching versus static file path resolution, enabling a bypass where middleware does not run but the static file is still served.\n\n## Details\n\nThe routing layer and the node-server static handler normalize request paths differently. The router preserves `%2F` as a literal string when matching routes, while the static handler decodes `%2F` into `/` before resolving the filesystem path.\n\nExample request:\n\n- `/admin%2Fsecret.html`\n\nThis may:\n- fail to match middleware intended for `/admin/*`, but\n- still be resolved by the static handler as `/admin/secret.html` under the configured static root.\n\nThis does not allow access outside the configured static root and is not a path traversal vulnerability.\n\n## Impact\n\nAn unauthenticated attacker could bypass route-based authorization protections for protected static resources by supplying paths containing encoded slashes.\n\nApplications relying solely on route-based middleware to protect static subpaths under the same static root may have exposed those resources.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "npm",
"name" : "@hono/node-server"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "1.19.10"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/honojs/node-server/security/advisories/GHSA-wc8c-qw6v-h7f6"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-29087"
}, {
"type" : "WEB",
"url" : "https://github.com/honojs/node-server/commit/455015be1697dd89974a68b70350ea7b2d126d2e"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/honojs/node-server"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-863" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2026-03-04T20:05:49Z",
"nvd_published_at" : "2026-03-06T18:16:19Z"
}
}