Skip to main content

Ac6 CVE-2026-4960

| EUVDEUVD-2026-16723 HIGH
Stack-based Buffer Overflow (CWE-121)
2026-03-27 VulDB GHSA-mcgx-8v57-hq28
7.4
CVSS 4.0 · Vendor: VulDB
View

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

  1. Access
    Authenticate to Tenda AC6 router
  2. Delivery
    Send POST request to /goform/WizardHandle
  3. Exploit
    Inject oversized payload in WANT/WANS parameter
  4. Execution
    Overflow stack buffer
  5. Impact
    Execute arbitrary code with device privileges

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A06:2021 - Vulnerable and Outdated Components
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

Tenda AC6 firmware 15.03.05.16. Attacker must have authenticated access to POST endpoint /goform/WizardHandle. Remote exploitation by manipulating WANT/WANS parameters causes stack-based buffer overflow. Authentication required; unauthenticated remote exploitation not possible.

Impact

The CVSS v3.1 vector (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) indicates network-accessible exploitation with low complexity requiring low-privilege authentication and no user interaction, yielding high impact across all CIA triad components. The temporal metrics show proof-of-concept code exists (E:P) with no official remediation (RL:X) and reasonable report confidence (RC:R). Publicly available exploit code exists, significantly lowering the skill barrier for exploitation. The requirement for authentication (PR:L) provides minimal protection since many Tenda routers ship with default credentials or weak password policies. Real-world risk is elevated because consumer routers are rarely patched, often Internet-facing for remote management, and represent high-value targets for botnet recruitment or network pivoting. The combination of public exploit availability, low attack complexity, network accessibility, and the embedded device patch deployment challenge creates substantial practical risk despite the authentication requirement.

Exploit ScenarioDerived

An authenticated attacker with low-privilege credentials (potentially obtained through credential stuffing, default passwords, or prior reconnaissance) connects to the Tenda AC6 router's web management interface over the network. The attacker crafts a malicious POST request to the /goform/WizardHandle endpoint with oversized WANT or WANS parameter values designed to overflow the stack buffer in the fromWizardHandle function. Publicly available exploit code exists demonstrating this technique, allowing the attacker to overwrite return addresses and execute arbitrary code with router firmware privileges, potentially installing persistent backdoors or incorporating the device into a botnet.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
No patch listed yet 0.0% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Mar 27, 2026

Stack-based buffer overflow in Tenda AC6 router firmware version 15.03.05.16 enables authenticated remote attackers to achieve code execution with high impact to confidentiality, integrity, and availability. The vulnerability resides in the fromWizardHandle function handling POST requests to /goform/WizardHandle, exploitable by manipulating WANT/WANS parameters. Publicly available exploit code exists, demonstrating the attack technique via a detailed proof-of-concept published on Notion. With a CVSS score of 8.8 and low attack complexity, this represents a significant risk to affected devices despite requiring low-privilege authentication.

RemediationAI

No vendor-released patch identified at time of analysis based on the available reference data. The CVSS remediation level indicator (RL:X) confirms no official fix is available. Until Tenda releases updated firmware addressing CVE-2026-4960, administrators should implement compensating controls including disabling remote management interfaces to prevent network-based exploitation, restricting administrative access to trusted IP ranges only, changing default credentials to strong unique passwords, and placing affected routers behind additional network segmentation. Monitor VulDB tracking pages at https://vuldb.com/?id.353837 and the vendor site at https://www.tenda.com.cn/ for future security updates. Consider replacing affected devices with alternative products if vendor support appears abandoned.

Affected VersionsENISA

AC6 15.03.05.16

Affected Packages

euvd ac6 no fix

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

The vulnerability affects Tenda AC6 wireless router firmware (CPE: cpe:2.3:a:tenda:ac6:*:*:*:*:*:*:*:*), specifically version 15.03.05.16. The root cause is CWE-121 (Stack-based Buffer Overflow) in the fromWizardHandle function within the /goform/WizardHandle endpoint that processes POST requests during router configuration. When processing the WANT or WANS parameters during the setup wizard workflow, insufficient bounds checking allows attacker-controlled input to overflow a stack-allocated buffer. This class of vulnerability can overwrite return addresses or function pointers on the call stack, enabling control of program execution flow. The issue is endemic to embedded device firmware that often lacks modern memory protection mechanisms like stack canaries, ASLR, or DEP.

Know when Ac6 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

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

Primary rating from Vendor (VulDB) · only source for this CVE.

CVSS VectorVendor: VulDB

Attack Vector
Network
Attack Complexity
Low
Attack Requirements
None
Privileges Required
Low
User Interaction
None
Vulnerable system: Confidentiality
High
Vulnerable system: Integrity
High
Vulnerable system: Availability
High
Subsequent system: Confidentiality
None
Subsequent system: Integrity
None
Subsequent system: Availability
None

Lifecycle Timeline

2
PoC Detected
Mar 31, 2026 - 20:58 vuln.today
Public exploit code
CVE Published
Mar 27, 2026 - 16:09 nvd
HIGH 7.4

DescriptionCVE.org

A vulnerability was determined in Tenda AC6 15.03.05.16. Affected is the function fromWizardHandle of the file /goform/WizardHandle of the component POST Request Handler. Executing a manipulation of the argument WANT/WANS can lead to stack-based buffer overflow. The attack can be executed remotely. The exploit has been publicly disclosed and may be utilized. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Executive ViewAI

Why It Matters

Tenda AC6 routers running firmware 15.03.05.16 are vulnerable to remote code execution that allows authenticated attackers to gain full control of the device, compromising network security and potentially exposing all connected systems and data. Organizations deploying these routers face immediate risk of unauthorized access, data interception, and network compromise, particularly concerning given the public availability of working attack code and the absence of a vendor patch.

Business Impact: Severe
Compensating Controls

Implement Web Application Firewall (WAF) rules to block POST requests to /goform/WizardHandle; restrict administrative access to the router's web interface to trusted internal IP addresses only via network segmentation; disable remote management features if not actively required; monitor for suspicious authentication attempts targeting router admin accounts; implement network access controls limiting the router's ability to initiate outbound connections to C2 infrastructure. If devices are internet-facing, immediately place them behind a reverse proxy or VPN gateway requiring additional authentication; consider temporary network isolation pending vendor patch release.

Threat Intelligence Overview

EPSS Score
0.0%
Top 86% exploitable
Exploit
POC
Public exploit code exists
Data Quality
6 sources
Confidence: High

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.

SignalValue
Severity HIGH
CISA KEV No
Public POC Yes
EPSS 0.0%
Patch available No
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision
Out-of-Cycle
Exploitation
Poc
System Exposure· derived
Open
Automatable
No
Human Impact
Very High
Technical Impact
Total

Priority Score

57
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +37
PoC: +20
Weaponized: 0
Threat intel: 0
Gov advisory: 0

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.

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy