{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/products/cx12l/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":8.8,"id":"CVE-2026-8138"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["CX12L"],"_cs_severities":["high"],"_cs_tags":["cve","buffer-overflow","tenda"],"_cs_type":"advisory","_cs_vendors":["Tenda"],"content_html":"\u003cp\u003eA stack-based buffer overflow vulnerability, identified as CVE-2026-8138, affects Tenda CX12L router with firmware version 16.03.53.12. The vulnerability resides in the \u003ccode\u003eformSetPPTPServer\u003c/code\u003e function within the \u003ccode\u003e/goform/SetPptpServerCfg\u003c/code\u003e file. The vulnerability was reported on 2026-05-08, and a proof-of-concept exploit is publicly available. Successful exploitation could allow a remote attacker to execute arbitrary code on the affected device, potentially leading to a full system compromise. This vulnerability poses a significant risk to users of the affected Tenda router model.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe attacker identifies a Tenda CX12L router running firmware version 16.03.53.12 exposed to the internet.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious HTTP request targeting the \u003ccode\u003e/goform/SetPptpServerCfg\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eThe crafted request includes an overly long string as input to the \u003ccode\u003eformSetPPTPServer\u003c/code\u003e function.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003eformSetPPTPServer\u003c/code\u003e function copies the attacker-supplied string into a fixed-size buffer on the stack without proper bounds checking.\u003c/li\u003e\n\u003cli\u003eThe buffer overflow overwrites adjacent stack memory, including the function\u0026rsquo;s return address.\u003c/li\u003e\n\u003cli\u003eWhen the \u003ccode\u003eformSetPPTPServer\u003c/code\u003e function returns, it attempts to jump to the overwritten return address, now controlled by the attacker.\u003c/li\u003e\n\u003cli\u003eThe attacker-controlled return address points to shellcode injected as part of the malicious HTTP request.\u003c/li\u003e\n\u003cli\u003eThe shellcode executes with the privileges of the affected process, allowing the attacker to execute arbitrary commands on the router.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of this vulnerability allows a remote attacker to execute arbitrary code on the Tenda CX12L router. This could allow the attacker to gain complete control over the device, potentially leading to the theft of sensitive information (such as Wi-Fi passwords), modification of router settings (such as DNS servers), or the use of the router as a bot in a larger botnet. Given the widespread use of Tenda routers, this vulnerability could impact a significant number of users.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u0026ldquo;Detect CVE-2026-8138 Exploitation Attempt — Tenda CX12L Buffer Overflow\u0026rdquo; to your SIEM to detect exploitation attempts targeting the vulnerable endpoint.\u003c/li\u003e\n\u003cli\u003eApply the Sigma rule \u0026ldquo;Detect Suspicious HTTP POST to SetPptpServerCfg Endpoint\u0026rdquo; to identify unusual activity.\u003c/li\u003e\n\u003cli\u003eMonitor web server logs for POST requests to \u003ccode\u003e/goform/SetPptpServerCfg\u003c/code\u003e with abnormally long parameter values to identify potential exploitation attempts.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-05-08T05:16:11Z","date_published":"2026-05-08T05:16:11Z","id":"/briefs/2026-05-tenda-cx12l-bo/","summary":"Tenda CX12L router version 16.03.53.12 is vulnerable to a stack-based buffer overflow in the formSetPPTPServer function of /goform/SetPptpServerCfg, allowing remote attackers to execute arbitrary code.","title":"Tenda CX12L Stack-Based Buffer Overflow Vulnerability (CVE-2026-8138)","url":"https://feed.craftedsignal.io/briefs/2026-05-tenda-cx12l-bo/"}],"language":"en","title":"CraftedSignal Threat Feed — CX12L","version":"https://jsonfeed.org/version/1.1"}