CVE-2026-55458 | Caddy WebSocket Upgrade reverseproxy.go handleUpgradeResponse request smuggling

October 28, 2026 Yanac

A vulnerability has been found in Caddy and classified as problematic. Affected is the function handleUpgradeResponse of the file modules/caddyhttp/reverseproxy/reverseproxy.go of the component WebSocket Upgrade. The manipulation leads to http request smuggling.

This vulnerability is uniquely identified as CVE-2026-55458. The attack is possible to be carried out remotely. No exploit exists.VulDB Recent EntriesRead More