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.

INFO

Published Date :

2026-03-20T09:37:07.206Z

Last Modified :

2026-03-20T11:40:27.956Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-33128 vulnerability.

Vendors Products
H3
  • H3
H3js
  • H3
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-33128.

URL Resource
https://github.com/h3js/h3/blob/52c82e18bb643d124b8b9ec3b1f62b081f044611/src/utils/internal/event-stream.ts#L170-L187 cve-icon cve-icon
https://github.com/h3js/h3/commit/7791538e15ca22437307c06b78fa155bb73632a6 cve-icon cve-icon
https://github.com/h3js/h3/security/advisories/GHSA-22cc-p3c6-wpvm cve-icon cve-icon
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