CVE-2026-118656
Echo: Open Redirect via Control-Character Prefix Defeating sanitizeURI
CVSS Score
6.1
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-601 |
| Vendor | labstack |
| Product | echo |
| Published | Oct 28, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
labstack / echo
>= 5.0.0, < 5.4.0 < 4.16.0
References
github.com: https://github.com/labstack/echo/security/advisories/GHSA-v753-g4cw-jm48 github.com: https://github.com/labstack/echo/commit/b838391e2eade87ae7e5a09d7bb5087bec271ec1 github.com: https://github.com/labstack/echo/commit/fc410094b2f3415cf2bf5204082137b205bfd5af github.com: https://github.com/labstack/echo/releases/tag/v4.16.0 github.com: https://github.com/labstack/echo/releases/tag/v5.4.0