CVE-2026-33128 h3 has a Server-Sent Events Injection via Unsanitized Newlines in Event Stream Fields

H3 is a minimal HTTP 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...

CVE-2026-33128 h3 has a Server-Sent Events Injection via Unsanitized Newlines in Event Stream Fields

H3 is a minimal HTTP 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...

CVE-2026-33128

CVE-2026-33128 is a reserved entry. The connected advisory for GHSA-22CC-P3C6-WPVM documents a vulnerability in the h3 library’s SSE streaming: createEventStream’s event-stream formatting functions (formatEventStreamMessage and formatEventStreamComment) fail to sanitize newlines in fields (id, ev...