{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-4906/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Tenda AC5"],"_cs_severities":["critical"],"_cs_tags":["cve-2026-4906","tenda","buffer-overflow","router"],"_cs_type":"advisory","_cs_vendors":["Tenda"],"content_html":"\u003cp\u003eCVE-2026-4906 is a critical vulnerability affecting Tenda AC5 version 15.03.06.47. This vulnerability is a stack-based buffer overflow located in the \u003ccode\u003edecodePwd\u003c/code\u003e function of the \u003ccode\u003e/goform/WizardHandle\u003c/code\u003e file, specifically within the POST Request Handler component. An unauthenticated, remote attacker can exploit this vulnerability by sending a crafted POST request with a manipulated \u003ccode\u003eWANT\u003c/code\u003e or \u003ccode\u003eWANS\u003c/code\u003e argument. Publicly available exploit code exists, increasing the risk of widespread exploitation. Successful exploitation allows attackers to execute arbitrary code on the affected device, potentially leading to complete system compromise. This poses a significant risk to organizations and home users relying on this 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 vulnerable Tenda AC5 router running firmware version 15.03.06.47.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious POST request targeting the \u003ccode\u003e/goform/WizardHandle\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eThe POST request includes the \u003ccode\u003eWANT\u003c/code\u003e or \u003ccode\u003eWANS\u003c/code\u003e argument, carefully crafted to cause a buffer overflow in the \u003ccode\u003edecodePwd\u003c/code\u003e function.\u003c/li\u003e\n\u003cli\u003eThe router processes the POST request and calls the \u003ccode\u003edecodePwd\u003c/code\u003e function.\u003c/li\u003e\n\u003cli\u003eDue to the insufficient bounds checking in \u003ccode\u003edecodePwd\u003c/code\u003e, the oversized \u003ccode\u003eWANT\u003c/code\u003e or \u003ccode\u003eWANS\u003c/code\u003e argument overwrites adjacent memory on the stack.\u003c/li\u003e\n\u003cli\u003eThe attacker overwrites critical data, such as the return address, with a malicious address pointing to injected shellcode.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003edecodePwd\u003c/code\u003e function returns, but instead of returning to the legitimate caller, it jumps to the attacker-controlled shellcode.\u003c/li\u003e\n\u003cli\u003eThe shellcode executes with the privileges of the web server process, allowing the attacker to perform arbitrary actions on the system, such as gaining a reverse shell or modifying router settings.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-4906 allows a remote attacker to execute arbitrary code on the vulnerable Tenda AC5 router. This could lead to complete compromise of the device, allowing the attacker to modify router settings, intercept network traffic, or use the router as a pivot point to attack other devices on the network. Given the widespread use of Tenda routers in home and small business environments, this vulnerability poses a significant risk to a large number of users.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eMonitor web server logs for POST requests to \u003ccode\u003e/goform/WizardHandle\u003c/code\u003e with unusually long \u003ccode\u003eWANT\u003c/code\u003e or \u003ccode\u003eWANS\u003c/code\u003e parameters. Deploy the Sigma rule \u003ccode\u003eTenda AC5 Suspicious WizardHandle POST Request\u003c/code\u003e to detect this activity.\u003c/li\u003e\n\u003cli\u003eApply any available patches or firmware updates released by Tenda to address CVE-2026-4906.\u003c/li\u003e\n\u003cli\u003eConsider deploying a web application firewall (WAF) with rules to block requests that exploit buffer overflow vulnerabilities, mitigating the risk even if a patch is not immediately available.\u003c/li\u003e\n\u003cli\u003eImplement network segmentation to limit the impact of a compromised router on other devices on the network.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-03T12:00:00Z","date_published":"2024-01-03T12:00:00Z","id":"https://feed.craftedsignal.io/briefs/2024-01-tenda-ac5-stack-overflow/","summary":"A stack-based buffer overflow vulnerability exists in Tenda AC5 version 15.03.06.47 allowing remote attackers to execute arbitrary code by manipulating the WANT/WANS argument in a POST request to /goform/WizardHandle.","title":"Tenda AC5 Stack-Based Buffer Overflow Vulnerability (CVE-2026-4906)","url":"https://feed.craftedsignal.io/briefs/2024-01-tenda-ac5-stack-overflow/"}],"language":"en","title":"CraftedSignal Threat Feed - Cve-2026-4906","version":"https://jsonfeed.org/version/1.1"}