CVE-2026-29085

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.12.4, when using streamSSE() in Streaming Helper, the event, id, and retry fields were not validated for carriage return (\r) or newline (\n) characters. Because the SSE protocol uses line breaks as field delimiters, this could allow injection of additional SSE fields within the same event frame if untrusted input was passed into these fields. This issue has been patched in version 4.12.4.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/honojs/hono/commit/f4123ed9ea3c7c52380cc99a079a4d773838846e	Patch
https://github.com/honojs/hono/security/advisories/GHSA-p6xx-57qc-3wxr	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-03-04 23:16

Updated : 2026-03-06 18:03

NVD link : CVE-2026-29085

Mitre link : CVE-2026-29085

CVE.ORG link : CVE-2026-29085

JSON object : View

Products Affected

hono

hono

CWE

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

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