Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
rexxars eventsource-encoder — eventsource-encoder: SSE event injection via unsanitized event and id fields
AV AC PR UI S C I A CVSS EPSS %ile KEV
N L N N U N L N 5.3 .0028 20.2 —
AFFECTED
Product Versions Fixed
eventsource-encoder < 1.0.2 – —
TIMELINE
May 5 Reserved by GitHub_M
May 26 EXPLOIT PUBLISHED — CVE-2026-44214 (rexxars eventsource-encoder). Public exploit reference added.
May 26 Published (CNA: GitHub_M)
Description
eventsource-encoder encodes events as well-formed EventSource/Server Sent Event (SSE) messages. Prior to 1.0.2, eventsource-encoder does not sanitize the event or id fields of an EventSourceMessage before serializing them. An attacker who controls either field can inject arbitrary Server-Sent Events line terminators (\n, \r, or \r\n) and thereby forge additional SSE fields or entire messages on the stream. This vulnerability is fixed in 1.0.2.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
|---|
| May 5, 2026 | Reserved | Reserved by GitHub_M |
| May 26, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-44214 (rexxars eventsource-encoder). Public exploit reference added. |
| May 26, 2026 | Published | Published (CNA: GitHub_M) |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| rexxars | eventsource-encoder | — | < 1.0.2 | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-44214 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.