EUVD-2026-35080
GHSA-pj5q-9vg7-6xmx
Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Primary rating from Vendor (VulDB) · only source for this CVE.
CVSS VectorVendor: VulDB
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Lifecycle Timeline
5DescriptionCVE.org
A flaw has been found in Tenda W20E 15.11.0.6. This issue affects the function formPortalAuth of the file /goform/PortalAuth of the component Web Management Interface. Executing a manipulation of the argument gotoUrl can lead to stack-based buffer overflow. The attack can be launched remotely. The exploit has been published and may be used.
AnalysisAI
Stack-based buffer overflow in Tenda W20E firmware 15.11.0.6 allows authenticated remote attackers to corrupt memory via the gotoUrl parameter handled by the formPortalAuth function in /goform/PortalAuth of the Web Management Interface. Publicly available exploit code exists, raising the likelihood of opportunistic targeting of internet-exposed router management interfaces, though no public exploit identified as actively exploited per CISA KEV at time of analysis.
Technical ContextAI
The Tenda W20E is an enterprise-grade wireless router; the affected component is its embedded web management interface, typically implemented in C on a Linux-based firmware. The vulnerability falls under CWE-121 (Stack-based Buffer Overflow), meaning the formPortalAuth handler copies the attacker-controlled gotoUrl HTTP parameter into a fixed-size stack buffer without proper length validation. On MIPS/ARM embedded targets like the W20E, such overflows typically allow overwriting the saved return address and gaining arbitrary code execution as the web server process, which on consumer/SMB routers commonly runs with root privileges. CPE cpe:2.3:a:tenda:w20e:*:*:*:*:*:*:*:* indicates all versions of the W20E product line should be considered affected pending vendor clarification.
RemediationAI
No vendor-released patch identified at time of analysis - the Tenda reference points only to the vendor homepage rather than a security advisory or firmware update. As compensating controls, administrators should immediately restrict access to the Web Management Interface by disabling remote/WAN-side administration (this prevents internet-based exploitation but does not address LAN-side attackers), placing the management interface behind a VPN or management VLAN, and enforcing strong administrative credentials to raise the bar for the PR:L precondition (trade-off: does not eliminate the vulnerability if credentials are phished or reused). Network operators should consider blocking inbound traffic to TCP port 80/443 on the WAN interface and monitoring web server logs for anomalous POST requests to /goform/PortalAuth with oversized gotoUrl values. Subscribe to updates at https://www.tenda.com.cn/ and https://vuldb.com/vuln/369143 for firmware availability.
Stack-based buffer overflow in Tenda W20E firmware 15.11.0.6(1068_1546_841)_CN_TDC enables remote low-privileged attacke
Stack-based buffer overflow in the Tenda W20E router (firmware 15.11.0.6) allows remote authenticated attackers to corru
Stack-based buffer overflow in the Tenda W20E router (firmware 15.11.0.6) allows remote authenticated attackers to corru
Stack-based buffer overflow in Tenda W20E firmware 15.11.0.6(1068_1546_841)_CN_TDC allows remote low-privileged attacker
Stack-based buffer overflow in Tenda W20E firmware 15.11.0.6(1068_1546_841)_CN_TDC allows authenticated remote attackers
Same weakness CWE-121 – Stack-based Buffer Overflow
View allSame technique Stack Overflow
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External POC / Exploit Code
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