{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/products/a8000ru-7.1cu.643_b20200521/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[{"cvss":9.8,"id":"CVE-2026-7240"}],"_cs_exploited":false,"_cs_products":["A8000RU 7.1cu.643_b20200521"],"_cs_severities":["critical"],"_cs_tags":["cve-2026-7240","command-injection","totolink","router","cgi"],"_cs_type":"advisory","_cs_vendors":["Totolink"],"content_html":"\u003cp\u003eA critical vulnerability, CVE-2026-7240, has been identified in Totolink A8000RU router firmware version 7.1cu.643_b20200521. This flaw resides within the CGI Handler component, specifically in the \u003ccode\u003esetVpnAccountCfg\u003c/code\u003e function of the \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e file. By exploiting this vulnerability, a remote attacker can inject arbitrary operating system commands by manipulating the \u003ccode\u003eUser\u003c/code\u003e argument. Publicly available exploit code exists, increasing the risk of widespread exploitation. This vulnerability poses a significant threat as it allows complete control of the affected device, potentially leading to network compromise and data exfiltration.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe attacker identifies a Totolink A8000RU router running firmware version 7.1cu.643_b20200521 accessible via the web interface.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious HTTP request targeting the \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eThe crafted request includes the \u003ccode\u003esetVpnAccountCfg\u003c/code\u003e function call with a payload injected into the \u003ccode\u003eUser\u003c/code\u003e argument. The payload contains OS commands to be executed on the router.\u003c/li\u003e\n\u003cli\u003eThe router\u0026rsquo;s CGI Handler processes the request without proper sanitization of the \u003ccode\u003eUser\u003c/code\u003e argument.\u003c/li\u003e\n\u003cli\u003eThe injected OS commands are executed with the privileges of the web server process.\u003c/li\u003e\n\u003cli\u003eThe attacker gains remote shell access to the router.\u003c/li\u003e\n\u003cli\u003eThe attacker leverages the compromised router to pivot within the network, potentially accessing sensitive data or other internal systems.\u003c/li\u003e\n\u003cli\u003eThe attacker could modify the router\u0026rsquo;s configuration, intercept network traffic, or use it as a launching point for further attacks.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-7240 allows a remote, unauthenticated attacker to execute arbitrary commands on the affected Totolink A8000RU router. This could lead to a complete compromise of the device, potentially exposing sensitive information, enabling unauthorized network access, and facilitating further attacks within the network. Given the ease of exploitation and the availability of public exploits, organizations using this router model are at high risk of experiencing significant security breaches.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eDetect Totolink A8000RU Command Injection Attempt\u003c/code\u003e to identify exploitation attempts against vulnerable Totolink routers. Enable webserver logging to capture the necessary request data.\u003c/li\u003e\n\u003cli\u003eApply the Sigma rule \u003ccode\u003eDetect Totolink A8000RU Malicious User Agent\u003c/code\u003e to detect potential exploit attempts based on modified User-Agent headers.\u003c/li\u003e\n\u003cli\u003eMonitor webserver logs for requests to \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e containing suspicious characters or command sequences in the \u003ccode\u003ecs-uri-query\u003c/code\u003e field, indicative of command injection attempts.\u003c/li\u003e\n\u003cli\u003eGiven the public availability of exploit code, organizations using the Totolink A8000RU 7.1cu.643_b20200521 are advised to replace the device if a patch is not available from the vendor.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-04-28T08:16:02Z","date_published":"2026-04-28T08:16:02Z","id":"/briefs/2026-04-totolink-cmd-injection/","summary":"CVE-2026-7240 is a critical OS command injection vulnerability in the Totolink A8000RU router that allows remote attackers to execute arbitrary commands by manipulating the 'User' argument in the 'setVpnAccountCfg' function.","title":"Totolink A8000RU OS Command Injection Vulnerability (CVE-2026-7240)","url":"https://feed.craftedsignal.io/briefs/2026-04-totolink-cmd-injection/"},{"_cs_actors":[],"_cs_cves":[{"cvss":9.8,"id":"CVE-2026-7154"}],"_cs_exploited":true,"_cs_products":["A8000RU 7.1cu.643_b20200521"],"_cs_severities":["critical"],"_cs_tags":["cve-2026-7154","command-injection","network-device"],"_cs_type":"threat","_cs_vendors":["Totolink"],"content_html":"\u003cp\u003eCVE-2026-7154 describes a critical vulnerability affecting the Totolink A8000RU router, specifically version 7.1cu.643_b20200521. The vulnerability is located in the \u003ccode\u003esetAdvancedInfoShow\u003c/code\u003e function within the \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e file, which handles CGI requests. An attacker can remotely exploit this flaw by manipulating the \u003ccode\u003etty_server\u003c/code\u003e argument, leading to OS command injection. This means an unauthenticated attacker can potentially execute arbitrary commands on the underlying operating system of the router. The exploit is publicly available, increasing the likelihood of exploitation in the wild. Successful exploitation allows complete control over the device.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe attacker identifies a vulnerable Totolink A8000RU router with the affected firmware version exposed to the internet.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious HTTP POST request targeting the \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eThe crafted request includes the \u003ccode\u003esetAdvancedInfoShow\u003c/code\u003e function call with a manipulated \u003ccode\u003etty_server\u003c/code\u003e argument containing an OS command injection payload.\u003c/li\u003e\n\u003cli\u003eThe webserver receives the crafted request and passes the \u003ccode\u003etty_server\u003c/code\u003e argument to the vulnerable function.\u003c/li\u003e\n\u003cli\u003eThe vulnerable function executes the attacker-supplied OS command due to insufficient input validation and sanitization.\u003c/li\u003e\n\u003cli\u003eThe injected command executes with the privileges of the web server process, typically root.\u003c/li\u003e\n\u003cli\u003eThe attacker gains arbitrary code execution on the router\u0026rsquo;s operating system.\u003c/li\u003e\n\u003cli\u003eThe attacker can then use this access to install malware, change router settings, or use the router as a pivot point for further attacks within the network.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-7154 allows a remote, unauthenticated attacker to execute arbitrary commands on the affected Totolink A8000RU router. This can lead to complete compromise of the device, potentially affecting all connected devices on the network. An attacker could steal sensitive information, disrupt network services, or use the compromised router as a botnet node. Given the public availability of the exploit, mass exploitation is a significant risk.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eMonitor web server logs for suspicious POST requests to \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e with unusual characters or command-like syntax in the \u003ccode\u003etty_server\u003c/code\u003e parameter, as this could indicate exploitation attempts (see example Sigma rule below).\u003c/li\u003e\n\u003cli\u003eImplement network intrusion detection system (IDS) rules to detect attempts to exploit this vulnerability by monitoring HTTP traffic for malicious payloads in the \u003ccode\u003etty_server\u003c/code\u003e parameter.\u003c/li\u003e\n\u003cli\u003eApply available patches or firmware updates provided by Totolink to address CVE-2026-7154 when they become available.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-23T12:00:00Z","date_published":"2024-01-23T12:00:00Z","id":"/briefs/2024-01-totolink-a8000ru-command-injection/","summary":"A remote OS command injection vulnerability exists in the Totolink A8000RU router version 7.1cu.643_b20200521, allowing attackers to execute arbitrary commands by manipulating the 'tty_server' argument in the 'setAdvancedInfoShow' function.","title":"Totolink A8000RU OS Command Injection Vulnerability (CVE-2026-7154)","url":"https://feed.craftedsignal.io/briefs/2024-01-totolink-a8000ru-command-injection/"},{"_cs_actors":[],"_cs_cves":[{"cvss":9.8,"id":"CVE-2026-7538"}],"_cs_exploited":false,"_cs_products":["A8000RU 7.1cu.643_b20200521"],"_cs_severities":["critical"],"_cs_tags":["command-injection","rce","totolink"],"_cs_type":"advisory","_cs_vendors":["Totolink"],"content_html":"\u003cp\u003eA critical vulnerability, tracked as CVE-2026-7538, has been identified in Totolink A8000RU router firmware version 7.1cu.643_b20200521. This vulnerability resides within the CGI handler component, specifically in the \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e file. The vulnerability arises from improper handling of the \u003ccode\u003eproto\u003c/code\u003e argument, which can be manipulated by an attacker to inject arbitrary operating system commands. Given that the attack can be initiated remotely and a public exploit is available, defenders should prioritize patching or implementing mitigations immediately. Exploitation could allow unauthenticated attackers to gain complete control over the affected device.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn attacker identifies a Totolink A8000RU router with the vulnerable firmware version (7.1cu.643_b20200521) exposed to the internet.\u003c/li\u003e\n\u003cli\u003eThe attacker sends a specially crafted HTTP request to the \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eThe HTTP request includes a malicious payload within the \u003ccode\u003eproto\u003c/code\u003e argument. This payload is designed to execute arbitrary OS commands.\u003c/li\u003e\n\u003cli\u003eThe CGI handler processes the request without proper sanitization of the \u003ccode\u003eproto\u003c/code\u003e argument.\u003c/li\u003e\n\u003cli\u003eThe unsanitized input from the \u003ccode\u003eproto\u003c/code\u003e argument is passed directly to a system call, resulting in OS command injection.\u003c/li\u003e\n\u003cli\u003eThe injected command executes with the privileges of the web server process.\u003c/li\u003e\n\u003cli\u003eThe attacker gains the ability to execute arbitrary code on the router, potentially including downloading and executing a reverse shell.\u003c/li\u003e\n\u003cli\u003eThe attacker establishes a persistent foothold and can perform further malicious activities, such as network reconnaissance, data exfiltration, or using the compromised device as part of a botnet.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-7538 grants attackers complete control over the affected Totolink A8000RU router. This can lead to a variety of malicious outcomes, including unauthorized access to the local network, data theft, and the use of the router as a node in a botnet for DDoS attacks or other malicious campaigns. Given the availability of a public exploit, widespread exploitation is possible if devices are not promptly patched or protected.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eApply available patches or firmware updates for Totolink A8000RU version 7.1cu.643_b20200521 to remediate CVE-2026-7538.\u003c/li\u003e\n\u003cli\u003eImplement network intrusion detection system (IDS) rules to detect malicious HTTP requests targeting the \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e endpoint with suspicious payloads in the \u003ccode\u003eproto\u003c/code\u003e argument.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eDetect Totolink A8000RU Command Injection Attempt\u003c/code\u003e to your SIEM to identify exploitation attempts based on suspicious HTTP requests.\u003c/li\u003e\n\u003cli\u003eMonitor web server logs for unusual activity or errors related to the \u003ccode\u003e/cgi-bin/cstecgi.cgi\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-03T12:00:00Z","date_published":"2024-01-03T12:00:00Z","id":"/briefs/2024-01-totolink-a8000ru-rce/","summary":"A remote OS command injection vulnerability exists in Totolink A8000RU version 7.1cu.643_b20200521 via manipulation of the 'proto' argument in the /cgi-bin/cstecgi.cgi CGI handler, potentially leading to complete system compromise.","title":"Totolink A8000RU OS Command Injection Vulnerability","url":"https://feed.craftedsignal.io/briefs/2024-01-totolink-a8000ru-rce/"}],"language":"en","title":"CraftedSignal Threat Feed — A8000RU 7.1cu.643_b20200521","version":"https://jsonfeed.org/version/1.1"}