What is the CVSS score of CVE-2026-3803?

CVE-2026-3803 has a CVSS 3.1 base score of 8.8 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.1%.

Which versions of I3 Firmware are affected by CVE-2026-3803?

A high-severity vulnerability (CVSS 8.8) affects Tenda i3 wireless routers, potentially allowing unauthorized access to network configuration and device control.

Is there a public PoC exploit available for CVE-2026-3803?

Yes, a public proof-of-concept exploit is available for CVE-2026-3803. Prioritise patching immediately. EPSS: 0.1%.

How to fix or mitigate CVE-2026-3803?

Within 24 hours: Identify and inventory all Tenda i3 1.0.0.6(2204) devices in your environment and isolate them from production networks if possible. Within 7 days: Implement network segmentation to restrict administrative access to affected devices and enable detailed logging of all access attempts. Contact Tenda for patch availability and timeline. Within 30 days: Deploy compensating controls or prepare for device replacement; establish a formal vendor communication plan for patch deployment once available.

I3 Firmware CVE-2026-3803

HIGH

Buffer Overflow (CWE-119)

2026-03-09 cna@vuldb.com

Buffer Overflow Stack Overflow I3 Firmware

8.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

8.8 HIGH

AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:56 vuln.today

PoC Detected

Mar 09, 2026 - 15:09 vuln.today

Public exploit code

CVE Published

Mar 09, 2026 - 06:16 nvd

HIGH 8.8

DescriptionCVE.org

A vulnerability was identified in Tenda i3 1.0.0.6(2204). This affects the function formWifiMacFilterGet of the file /goform/WifiMacFilterGet. The manipulation of the argument index leads to stack-based buffer overflow. It is possible to initiate the attack remotely. The exploit is publicly available and might be used.

AnalysisAI

Remote code execution in Tenda i3 firmware versions up to 1.0.0.6(2204) via stack-based buffer overflow in the WiFi MAC filter function allows unauthenticated attackers to achieve full system compromise over the network. Public exploit code exists for this vulnerability and no patch is currently available. The flaw requires only low complexity to exploit and affects the confidentiality, integrity, and availability of affected devices.

Technical ContextAI

Classified as CWE-119 (Buffer Overflow). Affects I3 Firmware. A vulnerability was identified in Tenda i3 1.0.0.6(2204). This affects the function formWifiMacFilterGet of the file /goform/WifiMacFilterGet. The manipulation of the argument index leads to stack-based buffer overflow. It is possible to initiate the attack remotely. The exploit is publicly available and might be used.

RemediationAI

Monitor vendor advisories for a patch. Enable ASLR, DEP/NX, and stack canaries where possible. Restrict network access to the affected service where possible.