How CVE-2025-2370 Works
The vulnerability in TOTOLINK EX1800T routers (up to firmware version 9.1.0cu.2112_B20220316) resides in the `setWiFiExtenderConfig` function within /cgi-bin/cstecgi.cgi. Attackers can exploit this flaw by sending a crafted HTTP request containing an overly long string in the `apcliSsid` parameter. Due to insufficient bounds checking, a stack-based buffer overflow occurs, allowing remote code execution (RCE) with root privileges. The exploit leverages improper input validation when processing Wi-Fi extender configurations, enabling attackers to overwrite critical stack memory and hijack control 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 '{"apcliSsid":"A"1024}'
2. ROP chain payload: Overwrite return address to execute shellcode.
3. Metasploit module: Auxiliary module for payload delivery.
Protection:
1. Patch firmware: Upgrade to TOTOLINK’s latest release.
2. Input validation: Sanitize `apcliSsid` length server-side.
3. Network hardening:
iptables -A INPUT -p tcp --dport 80 -m string --string "apcliSsid" --algo bm -j DROP
4. Binary protections: Enable ASLR and stack canaries.
Detection:
1. Log analysis: Monitor for oversized `apcliSsid` strings.
grep -E 'apcliSsid=.{500,}' /var/log/httpd.log
2. Snort rule:
alert tcp any any -> $HOME_NET 80 (msg:"CVE-2025-2370 Exploit Attempt"; content:"apcliSsid="; depth:1000;)
Debugging:
Disassemble vulnerable function:
gdb -q /usr/bin/cstecgi.cgi disas setWiFiExtenderConfig
Mitigation Script:
import requests
def check_vulnerability(ip):
try:
r = requests.post(f"http://{ip}/cgi-bin/cstecgi.cgi", json={"apcliSsid":"test"}, timeout=5)
return "200" in str(r.status_code)
except:
return False
References:
References:
Reported By: https://nvd.nist.gov/vuln/detail/CVE-2025-2370
Extra Source Hub:
Undercode
