Echo is a Go web framework. Prior to 4.16.0 and 5.4.0, sanitizeURI checks only the first two bytes of a redirect target before deciding whether it begins with an absolute-path separator pair. When AddTrailingSlash or RemoveTrailingSlash is configured with a redirect status, a slash, TAB, separator path form can evade the guard, be emitted in the Location header, and be normalized by a browser into an attacker-controlled host. This issue is fixed in 4.16.0 and 5.4.0.
History

Fri, 06 Nov 2026 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Moderate


Thu, 29 Oct 2026 18:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 29 Oct 2026 01:00:00 +0000

Type Values Removed Values Added
First Time appeared Labstack
Labstack echo
Vendors & Products Labstack
Labstack echo

Wed, 28 Oct 2026 20:30:00 +0000

Type Values Removed Values Added
Description Echo is a Go web framework. Prior to 4.16.0 and 5.4.0, sanitizeURI checks only the first two bytes of a redirect target before deciding whether it begins with an absolute-path separator pair. When AddTrailingSlash or RemoveTrailingSlash is configured with a redirect status, a slash, TAB, separator path form can evade the guard, be emitted in the Location header, and be normalized by a browser into an attacker-controlled host. This issue is fixed in 4.16.0 and 5.4.0.
Title Echo: Open Redirect via Control-Character Prefix Defeating sanitizeURI
Weaknesses CWE-601
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-10-28T20:12:13.757Z

Updated: 2026-10-29T17:23:39.728Z

Reserved: 2026-10-28T17:25:37.561Z

Link: CVE-2026-118656

cve-icon Vulnrichment

Updated: 2026-10-29T15:29:19.363Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-28T21:16:55.550

Modified: 2026-10-29T18:17:27.827

Link: CVE-2026-118656

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-10-28T20:12:13Z

Links: CVE-2026-118656 - Bugzilla