Review reviewHigh

CVE-2026-53779

webp-sh webp_server_go

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: 8.7
EPSS: 0.59%
CISA KEV: Not listed
Published: 2026.06.23

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.59%

Technical severityCVSS 8.7

Vulnerability overview

Affected product and versions

Product: webp-sh webp_server_go
Affected versions: < 0.15.0
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that webp-sh webp_server_go and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CWE: CWE-22