CVE-2026-53779

WebP Server Go through 0.14.4 contains a path traversal vulnerability on Windows that allows unauthenticated attackers to read files outside the configured IMG_PATH directory by sending requests with percent-encoded backslashes (%5C) that bypass the path.Clean() sanitization in handler/router.go. Attackers can exploit the discrepancy between Go's forward-slash-only path normalization and Windows file system APIs that treat backslashes and forward slashes as equivalent to access arbitrary files on the host filesystem accessible to the server process.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/webp-sh/webp_server_go/commit/eb3b5f9289b331cb639cd610b0d1c532d2cc24e0
https://github.com/webp-sh/webp_server_go/pull/451
https://www.vulncheck.com/advisories/webp-server-go-path-traversal-via-backslash-encoding-on-windows

Configurations

No configuration.

History

22 Jun 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-22 19:17

Updated : 2026-06-22 19:17

NVD link : CVE-2026-53779

Mitre link : CVE-2026-53779

CVE.ORG link : CVE-2026-53779

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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