What’s Vulnerable › Vulnerabilities

CVE-2026-118656: Echo: Open Redirect via Control-Character Prefix Defeating sanitizeURI

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-28 · updated 2026-10-29
• Weakness: CWE-601

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.

Affected products

• labstack echo: from 5.0.0, < 5.4.0; before 4.16.0

References

• https://github.com/labstack/echo/commit/b838391e2eade87ae7e5a09d7bb5087bec271ec1
• https://github.com/labstack/echo/commit/fc410094b2f3415cf2bf5204082137b205bfd5af
• https://github.com/labstack/echo/releases/tag/v4.16.0
• https://github.com/labstack/echo/releases/tag/v5.4.0
• https://github.com/labstack/echo/security/advisories/GHSA-v753-g4cw-jm48

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