CVE-2026-1143: TOTOLINK A3700R · Buffer Overflow
Affects TOTOLINK A3700RSource CVE Database V5
Public exploit available · CVSS 8.7 High.
Data as of 26 Oct 2026, 11:07 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 55% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 19 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CVSS exploit maturity: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| TOTOLINKA3700R | Affected
| Fixed in– |
AI-suggested
To mitigate CVE-2026-1143, organizations should immediately assess their network for the presence of TOTOLINK A3700R devices running the vulnerable firmware version 9.1.2u.5822_B20200513. If possible, upgrade to a patched firmware version once TOTOLINK releases an update addressing this vulnerability. In the absence of an official patch, implement network-level controls such as firewall rules to restrict access to the router’s management interfaces, especially blocking inbound traffic to the /cgi-bin/cstecgi.cgi endpoint from untrusted networks. Disable remote management features if not required. Employ network segmentation to isolate vulnerable devices from critical infrastructure. Monitor network traffic for unusual requests targeting the ssid parameter or attempts to exploit CGI scripts. Consider deploying intrusion detection/prevention systems (IDS/IPS) with signatures for this vulnerability or the public exploit. Regularly audit device configurations and logs for signs of compromise. Engage with TOTOLINK support for guidance and stay updated on firmware releases. Finally, educate network administrators about the risks of exposed embedded device interfaces and the importance of timely patching.
Description
A weakness has been identified in TOTOLINK A3700R 9.1.2u.5822_B20200513. This affects the function setWiFiEasyGuestCfg of the file /cgi-bin/cstecgi.cgi. Executing a manipulation of the argument ssid can lead to buffer overflow. The attack may be launched remotely. The exploit has been made available to the public and could be used for attacks.