Tenda W20E
CVE-2026-36819
HIGH
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessReach router HTTP management interface
-
DeliveryCraft POST to fromSetDhcpRules with oversized bindMACAddr
-
ExploitOverflow stack buffer in httpd handler
-
ExecutionCrash router process
-
ImpactSustained denial of service for downstream clients
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Stack buffer bounds checking
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | The attacker must have network reachability to the W20E's HTTP management interface and the device must be running firmware v15.11.0.6 (other versions unverified). No authentication, user interaction, or non-default configuration is required per the CVSS vector (AV:N/AC:L/PR:N/UI:N) - the fromSetDhcpRules handler is exposed by the default web UI. Practical limiting factor: most W20E deployments do not expose the management interface to the WAN by default, so real-world exploitation typically requires the attacker to be on the LAN or for an administrator to have explicitly enabled remote web management. |
| Impact | The CVSS vector AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H indicates a remote, unauthenticated, low-complexity attack with high availability impact only - consistent with a crash-style DoS rather than code execution. There is no EPSS score, KEV listing, or SSVC decision provided, and no public exploit identified at time of analysis; the only reference is a research repository (SemVulLLM) that appears to be an LLM-assisted vulnerability discovery dataset rather than a weaponized PoC. CWE-121 stack overflows on MIPS/ARM embedded targets sometimes escalate beyond DoS to RCE, but the CVSS impact metrics (C:N/I:N) suggest the reporter only validated a crash - defenders should treat RCE as a plausible but unconfirmed upside risk. Real-world priority is moderate-to-high for any W20E exposed to untrusted networks (especially if the WAN-side management interface is enabled), and low for devices restricted to a trusted LAN management VLAN. |
| Exploit ScenarioDerived | An attacker reachable on the network path to the router's web management interface sends a single crafted HTTP POST to the DHCP rule configuration endpoint with an oversized bindMACAddr value, overflowing a stack buffer inside fromSetDhcpRules and crashing the httpd process or the device itself. The result is loss of routing, DHCP, and wireless service for all downstream users until the device watchdog reboots or an admin power-cycles it; no authentication or user interaction is required, and the attack is trivially repeatable to sustain an outage. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Jun 09, 2026
Denial of service in Tenda W20E router firmware v15.11.0.6 allows unauthenticated remote attackers to crash the device by sending a crafted HTTP request that triggers a stack buffer overflow in the bindMACAddr parameter of the fromSetDhcpRules function. The CVSS 7.5 (AV:N/AC:L/PR:N/UI:N) reflects easy network-based exploitation with high availability impact but no confidentiality or integrity loss, and no public exploit identified at time of analysis beyond a research repository reference.
RemediationAI
No vendor-released patch identified at time of analysis; Tenda has not published an advisory or fixed firmware in the supplied references. As compensating controls, disable remote/WAN-side access to the router's web management interface (Tenda calls this 'Remote Web Management' under System Tools) so the fromSetDhcpRules endpoint is unreachable from the internet - this prevents external exploitation at the cost of losing remote admin convenience. Restrict LAN-side access to the management UI to a dedicated admin VLAN or specific source IPs via ACL where the device supports it, accepting that internal users on the same broadcast domain may still reach the endpoint. Monitor the third-party reference at https://github.com/xhh0124/SemVulLLM/tree/main/W20E/fromSetDhcpRules and Tenda's security page for a firmware release post-dating v15.11.0.6, and consider replacing end-of-support W20E units with a supported platform if Tenda does not issue a fix.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The Tenda W20E is an enterprise-grade wireless router whose web management interface processes DHCP rule configuration via the fromSetDhcpRules handler. The vulnerability is classified as CWE-121 (Stack-based Buffer Overflow), meaning the bindMACAddr HTTP parameter is copied into a fixed-size stack buffer without proper length validation, corrupting the saved return address or adjacent stack frame data. Tenda SOHO/SMB routers have a long history of similar unauthenticated stack overflows in their httpd/goahead-based web interfaces, where userspace input handlers frequently use unsafe string operations like strcpy or sprintf on attacker-controlled query parameters. The CPE data in the input is unpopulated (cpe:2.3:a:n/a:n/a:*) so the affected scope must be derived from the description: firmware build v15.11.0.6 on the W20E hardware platform.
Know when N A gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from Vendor (mitre) · only source for this CVE.
CVSS VectorVendor: mitre
Lifecycle Timeline
2DescriptionCVE.org
Shenzhen Tenda Technology Co., Ltd Tenda W20E v15.11.0.6 was discovered to contain a buffer overflow in the bindMACAddr parameter of the fromSetDhcpRules function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted HTTP request.
Executive ViewAI
Tenda W20E routers running firmware v15.11.0.6 contain a remote denial-of-service vulnerability accessible to any attacker with network access, enabling device crashes without authentication. Every affected router in your network infrastructure is a single-point failure risk, with no warning or user intervention preventing exploitation. Unpatched instances create immediate business continuity exposure across all dependent branch offices or remote sites.
No vendor-released patch identified at time of analysis. Interim mitigations: restrict network access to affected routers via firewall ACLs and layer-3 segmentation; disable WAN-accessible management ports if topology permits; monitor device availability and logs for exploitation attempts; maintain spare router inventory for rapid replacement; establish escalation procedure for unscheduled device failures.
Threat Intelligence Overview
NVD
CVE.org
EPSS
Vulnrichment
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
A stack-based buffer overflow occurs when a program writes more data to a buffer located on the stack than it was allocated to hold.
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)CVE.org
LibreNMS before 24.10.0 allows a remote attacker to execute arbitrary code via OS command injection involving AboutContr
Reachable assertion in Open5GS up to version 2.7.6 allows remote unauthenticated attackers to crash the Diameter CER han
A Command Injection issue in the payload build page in BYOB (Build Your Own Botnet) 2.0 allows attackers to execute arbi
Denial of service in Open5GS 2.7.6 and earlier allows network-adjacent attackers with low-privilege Diameter Gx peer acc
Denial of service in Open5GS HSS (Home Subscriber Server) versions 2.7.0 through 2.7.6 is triggered remotely by manipula
Remote command injection in Control Web Panel allows unauthenticated attackers to execute arbitrary OS commands as root
LINQPad before 5.52.01 Pro edition is vulnerable to Unsafe Deserialization in LINQPad.AutoRefManager::PopulateFromCache(
Remote code execution in dash-uploader (Python package for Plotly Dash) versions 0.1.0 through 0.7.0a2 allows unauthenti
Command injection in LiteLLM 1.18.10 lets attackers who can configure MCP (Model Context Protocol) servers supply arbitr
SQL injection in AzuraCast's backup restore flow (versions up to and including 0.23.7) lets an attacker achieve privileg
Arbitrary file read in Yu AI Code Mother v4.3 lets anonymous, remote attackers retrieve files outside the intended previ
Remote code execution in APScheduler (all versions through 3.10.x and 4.0.0a5) is achievable when applications deseriali
Exploit-DB