CRLF Injection Affecting hono package, versions >=3.8.0 <4.12.4
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-JS-HONO-15423717
- published5 Mar 2026
- disclosed5 Mar 2026
- creditSaad FELLAHI
Introduced: 5 Mar 2026
NewCVE-2026-29085 (opens in a new tab)How to fix?
Upgrade hono to version 4.12.4 or higher.
Overview
hono is an Ultrafast web framework for the Edges
Affected versions of this package are vulnerable to CRLF Injection via the writeSSE function when untrusted input containing carriage return or newline characters is passed to the event, id, or retry fields. An attacker can inject additional Server-Sent Events (SSE) fields within the same event frame by supplying specially crafted input.