CVE-2026-55629: Avwo Whistle

High severity, CVSS 8.7. EPSS: 0.7% chance of exploitation in the next 30 days.

Whistle is an HTTP, HTTP2, HTTPS, and WebSocket debugging proxy. Prior to 2.10.3, lib/service/service.js handles GET /cgi-bin/temp/get by reading req.query.filename, joining it to TEMP_FILES_PATH only when it matches the temporary file pattern, and otherwise passing the user-supplied filename directly to getFile, allowing a remote attacker to read arbitrary files such as /etc/passwd. This issue is reported as fixed in version 2.10.3.

Affected products

• Avwo Whistle: before 2.10.3 (fixed in 2.10.3)

Published 2026-07-16. Last modified 2026-07-17.