Which versions of Tenda are affected by CVE-2026-6123?

Tenda F451 routers running firmware 1.0.0.7 contain a high-severity stack buffer overflow that allows authenticated users with basic credentials to execute arbitrary code with administrative…

Is there a public PoC exploit available for CVE-2026-6123?

Yes, a public proof-of-concept exploit is available for CVE-2026-6123. Prioritise patching immediately. EPSS: 0.1%.

How to fix or mitigate CVE-2026-6123?

Within 24 hours: Identify all Tenda F451 devices in inventory and their current firmware versions; disable or restrict remote access to affected units if firmware is 1.0.0.7. Within 7 days: Contact Tenda support for patch status and availability timeline; implement network segmentation to limit router admin access to trusted management networks only. Within 30 days: Apply vendor-released patch immediately upon release; if no patch materializes, evaluate router replacement or isolation strategies.

Tenda CVE-2026-6123

Q: What is the CVSS score of CVE-2026-6123?

CVE-2026-6123 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: 0.1%.

EUVD-2026-21724 HIGH

Stack-based Buffer Overflow (CWE-121)

2026-04-12 VulDB

Tenda Stack Overflow Buffer Overflow

7.4

CVSS 4.0 · NVD

Severity by source

NVD 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 NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

Re-analysis Queued

Apr 29, 2026 - 20:07 vuln.today

cvss_changed

PoC Detected

Apr 29, 2026 - 20:00 vuln.today

Public exploit code

CVSS changed

Apr 12, 2026 - 09:22 NVD

8.8 (HIGH) 7.4 (HIGH)

Analysis Generated

Apr 12, 2026 - 08:51 vuln.today

EUVD ID Assigned

Apr 12, 2026 - 08:45 euvd

EUVD-2026-21724

Analysis Generated

Apr 12, 2026 - 08:45 vuln.today

CVE Published

Apr 12, 2026 - 08:15 nvd

HIGH 7.4

DescriptionCVE.org

A vulnerability was found in Tenda F451 1.0.0.7. This affects the function fromAddressNat of the file /goform/addressNat of the component httpd. Performing a manipulation of the argument entrys results in stack-based buffer overflow. Remote exploitation of the attack is possible. The exploit has been made public and could be used.

AnalysisAI

Stack-based buffer overflow in Tenda F451 router firmware 1.0.0.7 enables authenticated remote attackers to execute arbitrary code with high privileges via crafted 'entrys' parameter to the /goform/addressNat endpoint. The vulnerability resides in the fromAddressNat function of the httpd component. Public exploit code is available (GitHub), with EPSS indicating moderate exploitation probability. Requires low-privilege authentication (PR:L) but has low attack complexity (AC:L), making it accessible to attackers with basic router credentials.

Technical ContextAI

This vulnerability affects the httpd web server component in Tenda F451 wireless router firmware version 1.0.0.7 (CPE: cpe:2.3:a:tenda:f451). The flaw is a classic CWE-121 stack-based buffer overflow occurring in the fromAddressNat function when processing the Network Address Translation (NAT) configuration interface at /goform/addressNat. Stack-based buffer overflows occur when a program writes more data to a buffer on the call stack than it was allocated, overwriting adjacent memory including return addresses and function pointers. In embedded device web interfaces like this, input validation failures in CGI-style form handlers (goform endpoints) commonly lead to such memory corruption. The 'entrys' parameter likely accepts user-supplied NAT mapping entries without proper bounds checking before copying to a fixed-size stack buffer, allowing an attacker to overflow the buffer and control program execution flow.

RemediationAI

No vendor-released patch identified at time of analysis. Tenda's official website (https://www.tenda.com.cn/) should be monitored for firmware updates addressing CVE-2026-6123. Immediate risk mitigation steps include: disable remote administration features to eliminate external attack surface, ensuring the vulnerability is only exploitable from the local network; change default administrative credentials to strong, unique passwords to raise the authentication barrier; implement network segmentation to isolate the vulnerable device from critical assets; consider replacing the device with alternative router models receiving active security support if Tenda does not release timely patches. For enterprise environments, these consumer devices should not be deployed in production networks. VulDB tracking references are available at https://vuldb.com/vuln/356986 and https://vuldb.com/vuln/356986/cti for ongoing status monitoring.