CVE-2026-126210
What it is
@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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. Limited direct impact.
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: not scored yet.
- Severity: 5.3 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Weakness
- CWE-436
- Record status
- Received
Attack profile CVSS 3.1 · 5.3
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-126210.md and follow it. Check whether this project is affected by CVE-2026-126210. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/honojs/node-server/commit/3868998a805ae79216535ad3986c1e7228dee313
- https://github.com/honojs/node-server/commit/fb97395ec36af66567c76976e741110b02804d1c
- https://github.com/honojs/node-server/releases/tag/v1.19.18
- https://github.com/honojs/node-server/releases/tag/v2.1.6
- https://github.com/honojs/node-server/security/advisories/GHSA-jpvv-r467-5p4w
References
- https://github.com/honojs/node-server/commit/3868998a805ae79216535ad3986c1e7228dee313
- https://github.com/honojs/node-server/commit/fb97395ec36af66567c76976e741110b02804d1c
- https://github.com/honojs/node-server/releases/tag/v1.19.18
- https://github.com/honojs/node-server/releases/tag/v2.1.6
- https://github.com/honojs/node-server/security/advisories/GHSA-jpvv-r467-5p4w