Which versions of I12 are affected by CVE-2026-5609?

Tenda i12 router firmware 1.0.0.11(3862) contains a stack-based buffer overflow vulnerability (CVSS 8.8) in the WiFi SSID configuration interface that allows authenticated attackers to execute…

Is there a public PoC exploit available for CVE-2026-5609?

Yes, a public proof-of-concept exploit is available for CVE-2026-5609. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2026-5609?

Within 24 hours: Identify all Tenda i12 routers running firmware 1.0.0.11(3862) in your network inventory and isolate affected devices from production networks if possible. Within 7 days: Restrict network access to router management interfaces via firewall rules, VPN-only access, or ACLs to limit authentication attempts; change all default/administrative credentials. Within 30 days: Contact Tenda for patch availability timeline; evaluate replacement with devices receiving active security updates, or implement compensating controls if patching is unavailable.

I12 CVE-2026-5609

Q: What is the CVSS score of CVE-2026-5609?

CVE-2026-5609 has a CVSS 4.0 base score of 7.4 (High). CVSS vector: 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. EPSS exploitation probability: 0.0%.

EUVD-2026-19148 HIGH

Stack-based Buffer Overflow (CWE-121)

2026-04-06 VulDB

Buffer Overflow Stack Overflow Tenda I12

7.4

CVSS 4.0 · Vendor: VulDB

Severity by source

Vendor (VulDB) PRIMARY

7.4 HIGH

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

PoC Detected

Apr 07, 2026 - 13:20 vuln.today

Public exploit code

EUVD ID Assigned

Apr 06, 2026 - 01:45 euvd

EUVD-2026-19148

Analysis Generated

Apr 06, 2026 - 01:45 vuln.today

CVE Published

Apr 06, 2026 - 01:15 nvd

HIGH 7.4

DescriptionCVE.org

A flaw has been found in Tenda i12 1.0.0.11(3862). Affected by this vulnerability is the function formwrlSSIDset of the file /goform/wifiSSIDset of the component Parameter Handler. This manipulation of the argument index/wl_radio causes stack-based buffer overflow. It is possible to initiate the attack remotely. The exploit has been published and may be used.

AnalysisAI

Stack-based buffer overflow in Tenda i12 router firmware 1.0.0.11(3862) allows authenticated remote attackers to execute arbitrary code via the WiFi SSID configuration interface. The vulnerability is exploitable over the network with low complexity through manipulation of the 'index' or 'wl_radio' parameters in the formwrlSSIDset function. With publicly available exploit code (GitHub POC) and a CVSS score of 8.8, this presents immediate risk to exposed management interfaces. EPSS data not provided, but the combination of network accessibility, authentication bypass potential, and weaponized exploit elevates real-world risk.

Technical ContextAI

This vulnerability affects the Tenda i12 wireless router's web management interface, specifically the WiFi SSID configuration handler at endpoint /goform/wifiSSIDset. The root cause is CWE-121 (stack-based buffer overflow), occurring when the formwrlSSIDset function processes the 'index' or 'wl_radio' parameters without proper bounds checking. Stack-based buffer overflows allow attackers to overwrite return addresses and adjacent memory on the call stack, enabling control flow hijacking and arbitrary code execution. The affected product (cpe:2.3:a:tenda:i12) is a consumer-grade WiFi router where such vulnerabilities typically execute in the context of the web server process, often running with elevated privileges necessary for system configuration changes. The network-accessible attack vector (AV:N) combined with low attack complexity (AC:L) indicates the vulnerability can be triggered through standard HTTP/HTTPS requests to the management interface without requiring specialized conditions.

RemediationAI

No vendor-released patch identified at time of analysis. Users should immediately check the Tenda official support site at https://www.tenda.com.cn for firmware updates beyond version 1.0.0.11(3862) and apply any available security patches. As interim mitigations until patching: disable remote management access to the router's web interface, ensure the administrative interface is accessible only from trusted local networks (not WAN-facing), change default administrative credentials to complex passwords, and implement network segmentation to isolate the router's management plane. Organizations should consider replacing affected devices if vendor support is discontinued or patches are not forthcoming within an acceptable timeframe. Monitor vendor security advisories and the VulDB entry at https://vuldb.com/vuln/355400 for patch availability updates. Given the exploit's public availability at https://github.com/Litengzheng/vuldb_new/blob/main/i12/vul_107/README.md, these compensating controls should be implemented immediately.