CVE-2026-40876

The record

goshs is a SimpleHTTPServer written in Go. Prior to 2.0.0-beta.6, goshs contains an SFTP root escape caused by prefix-based path validation. An authenticated SFTP user can read from and write to filesystem paths outside the configured SFTP root, which breaks the intended jail boundary and can expose or modify unrelated server files. The SFTP subsystem routes requests through sftpserver/sftpserver.go into DefaultHandler.GetHandler() in sftpserver/handler.go, which forwards file operations into readFile, writeFile, listFile, and cmdFile. All of those sinks rely on sanitizePath() in sftpserver/helper.go. helper.go uses a raw string-prefix comparison, not a directory-boundary check. Because of that, if the configured root is /tmp/goshsroot, then a sibling path such as /tmp/goshsroot_evil/secret.txt incorrectly passes validation since it starts with the same byte prefix. This vulnerability is fixed in 2.0.0-beta.6.

Affected packages

Related vulnerabilities

• GHSA-5h6h-7rc9-3824 SFTP root escape via prefix-based path validation in goshs Same vulnerability
• CVE-2026-81163 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')… CWE-22
• CVE-2026-112049 Vita3K before build 4187 contains a path traversal (zip slip) vulnerability in… CWE-22
• CVE-2026-112005 WhoDB 0.104.0 before 0.135.0 contains a path traversal vulnerability that allows remote… CWE-22
• CVE-2026-61702 OpenPrinting CUPS is an open source printing system for Linux and other Unix-like… CWE-22
• CVE-2026-104871 The Angular SSR is a server-rise rendering tool for Angular applications. CWE-22
• CVE-2026-102991 Mako is a template library written in Python. CWE-22
• CVE-2026-101894 The decompress package for Node.js extracts archives. CWE-22