CVE-2026-118262
CVE-2026-118262 · Echo: WebSocket proxy can retain connections and handlers after client disconnect
This page contains facts from public vulnerability sources. Check the original advisory before updating.
Echo is a Go web framework. From 4.15.0 until 4.16.1 and 5.4.1, Echo's Proxy middleware can retain a handler, copy goroutines, and network connections after a WebSocket client disconnects when the upstream keeps its connection open. The raw proxy waits for both copy directions without reliably closing the peer connection when one direction ends, including when a rejected upgrade response uses HTTP keep-alive. Repeated connections can accumulate resources and cause denial of service, depending on proxy-route accessibility, upstream behavior, and connection deadlines. This issue is fixed in 4.16.1 and 5.4.1.
CVSS 8.2 · High · EPSS 0.3%
- Published
- Updated
Stack: system
Affected products and versions
echo
- Versions
- >= 4.15.0, < 4.16.1: Affected
- >= 5.0.0, < 5.4.1: Affected
No fix published
golang-github-labstack-echo Debian:12
- Versions
- 4.11.1-1
- 4.11.1-2
- 4.12.0-1
- 4.2.1-3
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
golang-github-labstack-echo Debian:13
- Versions
- 4.12.0-1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
golang-github-labstack-echo Debian:14
- Versions
- 4.12.0-1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
Original sources
- https://github.com/labstack/echo/security/advisories/GHSA-9969-6676-49h5
- https://github.com/labstack/echo/commit/1855061e572ae9dab727c811d8382f266bfbaaec
- https://github.com/labstack/echo/commit/3fb0ba7e17645bb65611e2a08875d0a2f65c421f
- https://github.com/labstack/echo/releases/tag/v4.16.1
- https://github.com/labstack/echo/releases/tag/v5.4.1
- https://nvd.nist.gov/vuln/detail/CVE-2026-118262