CVE-2026-55677
Echo: Encoded slash (%2F) bypasses route-level protection and exposes static files
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-22 |
| Vendor | labstack |
| Product | echo |
| Published | Jun 26, 2026 |
| Last Updated | Jun 26, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
labstack / echo
< 4.15.3 >= 5.0.0, < 5.2.0