Which versions of T6 Firmware are affected by CVE-2025-6916?

CVE-2025-6916 presents significant security risk, a improper authentication vulnerability rated CVSS 8.8.

Is there a public PoC exploit available for CVE-2025-6916?

Yes, a public proof-of-concept exploit is available for CVE-2025-6916. Prioritise patching immediately. EPSS: 0.1%.

How to fix or mitigate CVE-2025-6916?

Within 7 days: Identify all affected systems and apply vendor patches promptly. Audit authentication configurations and rotate any potentially compromised credentials.

T6 Firmware CVE-2025-6916

Q: What is the CVSS score of CVE-2025-6916?

CVE-2025-6916 has a CVSS 4.0 base score of 7.4 (High). CVSS vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/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-2025-19554 HIGH

Improper Authentication (CWE-287)

2025-06-30 cna@vuldb.com

Authentication Bypass T6 Firmware TOTOLINK

7.4

CVSS 4.0 · NVD

Severity by source

NVD PRIMARY

7.4 HIGH

CVSS:4.0/AV:A/AC:L/AT:N/PR:N/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

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Lifecycle Timeline

CVSS changed

Apr 29, 2026 - 01:11 NVD

8.8 (HIGH) 7.4 (HIGH)

EUVD ID Assigned

Mar 16, 2026 - 01:25 euvd

EUVD-2025-19554

Analysis Generated

Mar 16, 2026 - 01:25 vuln.today

PoC Detected

Jul 07, 2025 - 14:41 vuln.today

Public exploit code

CVE Published

Jun 30, 2025 - 17:15 cve.org

HIGH 7.4

CVE Published

Jun 30, 2025 - 17:15 nvd

HIGH 8.8

DescriptionCVE.org

A vulnerability, which was classified as critical, was found in TOTOLINK T6 4.1.5cu.748_B20211015. This affects the function Form_Login of the file /formLoginAuth.htm. The manipulation of the argument authCode/goURL leads to missing authentication. The attack needs to be initiated within the local network. The exploit has been disclosed to the public and may be used.

AnalysisAI

Authentication bypass in TOTOLINK T6 router firmware 4.1.5cu.748_B20211015 allows adjacent network attackers to manipulate the authCode or goURL parameters to bypass authentication on the /formLoginAuth.htm endpoint. The vulnerability enables unauthorized access to administrative functions without credentials. Publicly available exploit code exists, but no active exploitation has been confirmed.