sse-channel: SSE Injection via unsanitized event fields — CVE-2026-44217

Summary

### Impact Implementations that allows user-provided values to be passed to `event`, `retry` or `id` fields would be susceptible to event spoofing, where an attacker could inject arbitrary messages into the stream. - **Event Spoofing:** Attacker can inject arbitrary SSE events into the stream - **Client-side Manipulation:** Injected events can trigger unintended behavior in frontend JavaScript EventSource listeners…

Product

npm: sse-channel

What to do

General, cautious steps (verify details in the official source):

• Review exposure and plan remediation based on risk and environment.
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source
• CVE Record
• NVD

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