CVE-2026-118262

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

No CVSS.

References

Link	Resource
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://github.com/labstack/echo/security/advisories/GHSA-9969-6676-49h5

Configurations

No configuration.

History

28 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-28 19:17

Updated : 2026-10-29 15:15

NVD link : CVE-2026-118262

Mitre link : CVE-2026-118262

CVE.ORG link : CVE-2026-118262

JSON object : View

Products Affected

No product.

CWE

CWE-772

Missing Release of Resource after Effective Lifetime

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