CVE-2026-33128

Severity CVSS v4.0:

Pending analysis

Type:

CWE-93 Improper Neutralization of CRLF Sequences ('CRLF Injection')

Publication date:

20/03/2026

Last modified:

20/03/2026

Description

H3 is a minimal H(TTP) framework. In versions prior to 1.15.6 and between 2.0.0 through 2.0.1-rc.14, createEventStream is vulnerable to Server-Sent Events (SSE) injection due to missing newline sanitization in formatEventStreamMessage() and formatEventStreamComment(). An attacker who controls any part of an SSE message field (id, event, data, or comment) can inject arbitrary SSE events to connected clients. This issue is fixed in versions 1.15.6 and 2.0.1-rc.15.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N CVSS v3.1 Severity and Metrics:

Base Score: 7.50 HIGH
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N

Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): Low
Integrity (I): High
Availability (A): None

Base Score 3.x

7.50

Severity 3.x

HIGH

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:h3:h3::::::node.js::*		1.15.6 (excluding)
cpe:2.3:a:h3:h3:2.0.0:::::node.js::
cpe:2.3:a:h3:h3:2.0.1:rc10::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc11::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc12::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc13::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc14::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc2::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc3::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc4::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc5::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc6::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc7::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc8::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc9::::node.js::*

To consult the complete list of CPE names with products and versions, see this page

CPE	From	Up to
cpe:2.3:a:h3:h3::::::node.js::*		1.15.6 (excluding)
cpe:2.3:a:h3:h3:2.0.0:::::node.js::
cpe:2.3:a:h3:h3:2.0.1:rc10::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc11::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc12::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc13::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc14::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc2::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc3::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc4::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc5::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc6::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc7::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc8::::node.js::*
cpe:2.3:a:h3:h3:2.0.1:rc9::::node.js::*

CVE-2026-33128

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools