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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-33128 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/h3js/h3/blob/52c82e18bb643d124b8b9ec3b1f62b081f044611/src/utils/internal/event-stream.ts#L170-L187 GitHub, Inc.
https://github.com/h3js/h3/commit/7791538e15ca22437307c06b78fa155bb73632a6 GitHub, Inc.
https://github.com/h3js/h3/security/advisories/GHSA-22cc-p3c6-wpvm GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-93 Improper Neutralization of CRLF Sequences ('CRLF Injection') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-33128
NVD Published Date:
03/20/2026
NVD Last Modified:
03/20/2026
Source:
GitHub, Inc.