How CVE-2025-2369 Works
The vulnerability exists in the `setPasswordCfg` function within `/cgi-bin/cstecgi.cgi` of TOTOLINK EX1800T firmware versions up to 9.1.0cu.2112_B20220316. Attackers can exploit this flaw by sending a malicious HTTP request with an overly long `admpass` parameter, triggering a stack-based buffer overflow. Due to insufficient bounds checking, this overflow corrupts adjacent memory, potentially allowing remote code execution (RCE) with root privileges. The exploit is remotely accessible without authentication, making it critical. Publicly disclosed PoC exploits leverage crafted payloads to overwrite return addresses and hijack execution flow.
DailyCVE Form
Platform: TOTOLINK EX1800T
Version: ≤9.1.0cu.2112_B20220316
Vulnerability: Stack overflow
Severity: Critical
Date: 04/07/2025
What Undercode Say:
Exploitation
1. Craft malicious HTTP POST request:
curl -X POST http://<TARGET_IP>/cgi-bin/cstecgi.cgi -d '{"admpass":"$(python -c 'print("A"1024)')"}'
2. Metasploit module (if available):
use exploit/linux/http/totolink_ex1800t_bufferoverflow set RHOST <TARGET_IP> exploit
Detection
1. Check firmware version:
cat /etc/version | grep "9.1.0cu"
2. Log analysis for overflow attempts:
grep -i "cstecgi.cgi" /var/log/messages
Mitigation
1. Patch firmware:
- Upgrade to version >9.1.0cu.2112_B20220316.
2. Input validation:
// Pseudocode fix
if (strlen(admpass) > MAX_LEN) {
exit(1);
}
3. Network controls:
iptables -A INPUT -p tcp --dport 80 -s !TRUSTED_IP -j DROP
Debugging
1. Crash analysis with GDB:
gdb -q /usr/bin/cstecgi
run < <(python -c 'print("A"1024)')
2. Stack canary check:
checksec --file=/cgi-bin/cstecgi.cgi
References
References:
Reported By: https://nvd.nist.gov/vuln/detail/CVE-2025-2369
Extra Source Hub:
Undercode
