{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-4566/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["critical"],"_cs_tags":["cve-2026-4566","buffer-overflow","router","rce"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eA stack-based buffer overflow vulnerability has been discovered in the Belkin F9K1122 router, specifically version 1.00.33. The vulnerability resides within the \u003ccode\u003eformWISP5G\u003c/code\u003e function located in the \u003ccode\u003e/goform/formWISP5G\u003c/code\u003e file. Successful exploitation involves manipulating the \u003ccode\u003ewebpage\u003c/code\u003e argument, leading to arbitrary code execution. This vulnerability is remotely exploitable, making it a significant threat. Publicly available exploit code exists, increasing the likelihood of exploitation. The vendor was notified but has not responded, indicating a lack of timely patching. This poses a high risk to users of the affected Belkin router model.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker identifies a vulnerable Belkin F9K1122 router running firmware version 1.00.33.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious HTTP request targeting the \u003ccode\u003e/goform/formWISP5G\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eWithin the HTTP request, the \u003ccode\u003ewebpage\u003c/code\u003e argument is manipulated to contain a payload exceeding the buffer size.\u003c/li\u003e\n\u003cli\u003eThe router\u0026rsquo;s web server processes the request and passes the attacker-controlled input to the \u003ccode\u003eformWISP5G\u003c/code\u003e function.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003eformWISP5G\u003c/code\u003e function attempts to copy the oversized \u003ccode\u003ewebpage\u003c/code\u003e argument into a fixed-size buffer on the stack.\u003c/li\u003e\n\u003cli\u003eA stack-based buffer overflow occurs, overwriting adjacent memory regions, including the return address.\u003c/li\u003e\n\u003cli\u003eThe attacker gains control of the program execution flow by redirecting it to attacker-controlled code.\u003c/li\u003e\n\u003cli\u003eThe attacker executes arbitrary code on the router, potentially gaining complete control of the device.\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 Belkin F9K1122 router. This can lead to a complete compromise of the device, allowing the attacker to modify router settings, intercept network traffic, or use the router as a pivot point for further attacks within the network. Given the wide use of these routers in home and small business environments, a successful widespread attack could impact thousands of users. The absence of a vendor patch exacerbates the risk.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eImplement a web application firewall (WAF) rule to detect and block requests with excessively long \u003ccode\u003ewebpage\u003c/code\u003e arguments to the \u003ccode\u003e/goform/formWISP5G\u003c/code\u003e endpoint, mitigating exploitation attempts (Attack Chain step 3).\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule provided to detect suspicious web requests targeting the vulnerable endpoint (see \u0026ldquo;Belkin Router RCE Attempt\u0026rdquo; rule).\u003c/li\u003e\n\u003cli\u003eMonitor web server logs for unusual activity related to the \u003ccode\u003e/goform/formWISP5G\u003c/code\u003e endpoint (Attack Chain step 4).\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-03-23T03:16:00Z","date_published":"2026-03-23T03:16:00Z","id":"/briefs/2026-03-belkin-rce/","summary":"A stack-based buffer overflow vulnerability exists in Belkin F9K1122 version 1.00.33, allowing remote attackers to execute arbitrary code by manipulating the 'webpage' argument in the 'formWISP5G' function.","title":"Belkin F9K1122 Router Stack-Based Buffer Overflow","url":"https://feed.craftedsignal.io/briefs/2026-03-belkin-rce/"}],"language":"en","title":"CraftedSignal Threat Feed — Cve-2026-4566","version":"https://jsonfeed.org/version/1.1"}