Which versions of Tenda F456 are affected by EUVD-2026-25726?

A buffer overflow in Tenda F456 router firmware (version 1.0.0.5) enables authenticated attackers to execute arbitrary code, creating a direct threat to network perimeter security and potentially…

Is there a public PoC exploit available for EUVD-2026-25726?

Yes, a public proof-of-concept exploit is available for EUVD-2026-25726. Prioritise patching immediately. EPSS: 0.1%.

How to fix or mitigate EUVD-2026-25726?

Within 24 hours: inventory all Tenda F456 routers in production and identify firmware version. Within 7 days: contact Tenda support to confirm patch availability timeline and assess whether affected devices can be isolated or decommissioned. Within 30 days: if no patch is released, implement compensating controls (network segmentation, WAN-only admin access restrictions, disable SafeUrlFilter if operationally feasible) or plan replacement with patched firmware version or alternative router.

Tenda F456 EUVD-2026-25726

Q: What is the CVSS score of EUVD-2026-25726?

EUVD-2026-25726 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%.

| CVE-2026-7056 HIGH

Classic Buffer Overflow (CWE-120)

2026-04-26 VulDB

Buffer Overflow Tenda

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

PoC Detected

Apr 29, 2026 - 22:18 vuln.today

Public exploit code

Analysis Updated

Apr 26, 2026 - 22:28 vuln.today

v2 (cvss_changed)

Re-analysis Queued

Apr 26, 2026 - 22:22 vuln.today

cvss_changed

CVSS changed

Apr 26, 2026 - 22:22 NVD

8.8 (HIGH) 7.4 (HIGH)

Analysis Generated

Apr 26, 2026 - 19:15 vuln.today

EUVD ID Assigned

Apr 26, 2026 - 18:45 euvd

EUVD-2026-25726

Analysis Generated

Apr 26, 2026 - 18:45 vuln.today

CVE Published

Apr 26, 2026 - 18:30 nvd

HIGH 7.4

DescriptionCVE.org

A vulnerability was detected in Tenda F456 1.0.0.5. Impacted is the function fromSafeUrlFilter of the file /goform/SafeUrlFilter of the component httpd. The manipulation of the argument page results in buffer overflow. The attack may be performed from remote. The exploit is now public and may be used.

AnalysisAI

Buffer overflow in Tenda F456 router firmware 1.0.0.5 allows authenticated remote attackers to achieve arbitrary code execution with high impact to confidentiality, integrity, and availability. The vulnerability resides in the SafeUrlFilter functionality of the httpd web server component, triggered by manipulating the 'page' parameter. A public proof-of-concept exploit is available on GitHub, significantly lowering the barrier to exploitation, though no CISA KEV listing or widespread exploitation has been confirmed at time of analysis.

Technical ContextAI

This is a classic stack-based buffer overflow (CWE-120) in the httpd daemon of Tenda F456 wireless router firmware. The vulnerable function fromSafeUrlFilter in /goform/SafeUrlFilter fails to properly validate the length of the 'page' parameter before copying it into a fixed-size buffer. When processing HTTP POST/GET requests to this endpoint, an attacker can supply an oversized 'page' value that overwrites adjacent memory, potentially hijacking program execution flow. The httpd component typically runs with elevated privileges on embedded router platforms, making successful exploitation particularly dangerous. The CPE string cpe:2.3:a:tenda:f456 confirms this affects the application-level firmware rather than hardware-specific vulnerabilities.

RemediationAI

No vendor-released patch has been identified at time of analysis. Users should immediately check the Tenda support website (https://www.tenda.com.cn/) for firmware updates newer than 1.0.0.5, though no specific patched version has been confirmed. As compensating controls until a patch is available: (1) Change the router admin password to a strong, unique credential if using default or weak passwords - this directly mitigates the PR:L requirement by preventing unauthorized authenticated access; (2) Disable remote administration features and restrict web interface access to the local LAN only, blocking the AV:N attack vector from internet-based attackers; (3) Place the router behind a separate firewall or network segmentation if possible, though this is impractical for most home users; (4) Monitor router logs for unusual administrative activity or unexpected reboots indicating compromise. Trade-off: Disabling remote admin improves security but prevents legitimate remote management. Consider replacing the device with a model from a vendor with active security support if Tenda does not release a patch within a reasonable timeframe, as unpatched buffer overflows in gateway devices pose unacceptable risk to the entire network.