๐Ÿ” CVE Alert

CVE-2026-126210

MEDIUM 5.3

@hono/node-server: Backslash in the request path is parsed as a path separator, bypassing path-based access control at a reverse proxy

CVSS Score
5.3
EPSS Score
0.0%
EPSS Percentile
0th

@hono/node-server allows running the Hono application on Node.js. Prior to 1.19.18 and from 2.0.0 until 2.1.6, the server passes a raw request-target containing a backslash in its path to the WHATWG URL parser, which treats the backslash as a path separator and resolves dot segments. A reverse proxy, load balancer, or web application firewall that preserves the backslash and applies path-based rules to the original request can therefore permit a request that the application normalizes to a blocked route. This lets an unauthenticated client reach route content that the upstream component was intended to deny, while Hono application access controls are unaffected because they operate on the normalized path. This issue is fixed in versions 1.19.18 and 2.1.6.

CWE CWE-436
Vendor honojs
Product node-server
Published Nov 12, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

Affected Versions

honojs / node-server
>= 2.0.0, < 2.1.6 < 1.19.18

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/honojs/node-server/security/advisories/GHSA-jpvv-r467-5p4w github.com: https://github.com/honojs/node-server/commit/3868998a805ae79216535ad3986c1e7228dee313 github.com: https://github.com/honojs/node-server/commit/fb97395ec36af66567c76976e741110b02804d1c github.com: https://github.com/honojs/node-server/releases/tag/v1.19.18 github.com: https://github.com/honojs/node-server/releases/tag/v2.1.6