CVE-2026-5851: OS Command Injection in Totolink A7100RU
CVE-2026-5851 is a critical OS command injection vulnerability in the Totolink A7100RU router firmware version 7. 4cu. 2313_b20191024. The flaw exists in the setUPnPCfg function within the /cgi-bin/cstecgi. cgi CGI handler, where manipulation of the 'enable' argument allows remote attackers to execute arbitrary OS commands. The vulnerability is remotely exploitable without authentication and has a high CVSS 4. 0 score of 9. 3. Although the exploit code has been publicly released, no official patch or remediation guidance is currently available from the vendor. There is no indication that this is a cloud service, so remediation depends on vendor firmware updates.
AI Analysis
Technical Summary
This vulnerability affects the Totolink A7100RU router firmware 7.4cu.2313_b20191024. It arises from improper input validation in the setUPnPCfg function of the /cgi-bin/cstecgi.cgi CGI handler, specifically in the 'enable' parameter. This allows an unauthenticated remote attacker to perform OS command injection, potentially leading to full system compromise. The CVSS 4.0 vector indicates network attack vector, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The vulnerability is publicly disclosed with exploit code available, but no official patch or mitigation has been published by Totolink as of now.
Potential Impact
Successful exploitation allows remote attackers to execute arbitrary operating system commands on the affected device without authentication. This can lead to full compromise of the router, including unauthorized control, data theft, or disruption of network services. Given the critical CVSS score of 9.3, the impact on confidentiality, integrity, and availability is high.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or temporary mitigation has been published by Totolink, users should monitor for vendor updates. Until a patch is available, restricting access to the router's management interface from untrusted networks and disabling UPnP if possible may reduce exposure.
CVE-2026-5851: OS Command Injection in Totolink A7100RU
Description
CVE-2026-5851 is a critical OS command injection vulnerability in the Totolink A7100RU router firmware version 7. 4cu. 2313_b20191024. The flaw exists in the setUPnPCfg function within the /cgi-bin/cstecgi. cgi CGI handler, where manipulation of the 'enable' argument allows remote attackers to execute arbitrary OS commands. The vulnerability is remotely exploitable without authentication and has a high CVSS 4. 0 score of 9. 3. Although the exploit code has been publicly released, no official patch or remediation guidance is currently available from the vendor. There is no indication that this is a cloud service, so remediation depends on vendor firmware updates.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability affects the Totolink A7100RU router firmware 7.4cu.2313_b20191024. It arises from improper input validation in the setUPnPCfg function of the /cgi-bin/cstecgi.cgi CGI handler, specifically in the 'enable' parameter. This allows an unauthenticated remote attacker to perform OS command injection, potentially leading to full system compromise. The CVSS 4.0 vector indicates network attack vector, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The vulnerability is publicly disclosed with exploit code available, but no official patch or mitigation has been published by Totolink as of now.
Potential Impact
Successful exploitation allows remote attackers to execute arbitrary operating system commands on the affected device without authentication. This can lead to full compromise of the router, including unauthorized control, data theft, or disruption of network services. Given the critical CVSS score of 9.3, the impact on confidentiality, integrity, and availability is high.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or temporary mitigation has been published by Totolink, users should monitor for vendor updates. Until a patch is available, restricting access to the router's management interface from untrusted networks and disabling UPnP if possible may reduce exposure.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-04-08T19:19:56.874Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69d745461cc7ad14da533b28
Added to database: 4/9/2026, 6:20:54 AM
Last enriched: 4/16/2026, 12:25:25 PM
Last updated: 5/23/2026, 7:24:17 PM
Views: 85
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