Echo: Encoded slash (%2F) bypasses route-level protection and exposes static...

7.5 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Description

Echo is a Go web framework. Prior to 4.15.3 and 5.2.0, Echo's router and static file handler disagree on URL path decoding. The router matches routes using the raw encoded path (preserving %2F as-is), while StaticDirectoryHandler unescapes %2F to / before resolving filesystem paths. This allows an attacker to bypass route-level access controls and read static files without authorization. This vulnerability is fixed in 4.15.3 and 5.2.0.

Basic Information

ID CVE-2026-55677

Source GitHub_M

Published Jun 26, 2026 at 16:15

Affected Product

Vendor labstack

Product echo

Version < 4.15.3

Affected Versions labstack echo < 4.15.3
labstack echo >= 5.0.0, < 5.2.0

CWE Classification

CWE-22

References

github.com /labstack/echo/security/advisories/GHSA-vfp3-v2gw-7wfq

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    "published": "2026-06-26T16:15:55.633Z",
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Echo: Encoded slash (%2F) bypasses route-level protection and exposes static files_CVE-2026-55677