CVE-2025-7912
Published: 20 July 2025
Summary
CVE-2025-7912 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Totolink T6 Firmware. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 29.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly validates crafted inputs like the 's' argument to the recvSlaveUpgstatus function in the MQTT Service, preventing buffer overflow exploitation.
Enforces memory protections such as address space layout randomization and stack guards to mitigate unauthorized code execution from buffer overflows in the MQTT Service.
Requires identification, reporting, and patching of the specific buffer overflow flaw in TOTOLINK T6 firmware version 4.1.5cu.748_B20211015.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Buffer overflow in exposed MQTT service enables remote code execution from low-priv network access (T1190/T1210) and achieves privilege escalation to full device control (T1068).
NVD Description
A vulnerability, which was classified as critical, has been found in TOTOLINK T6 4.1.5cu.748_B20211015. This issue affects the function recvSlaveUpgstatus of the component MQTT Service. The manipulation of the argument s leads to buffer overflow. The attack may be initiated…
more
remotely. The exploit has been disclosed to the public and may be used.
Deeper analysisAI
CVE-2025-7912 is a critical buffer overflow vulnerability affecting the TOTOLINK T6 router running firmware version 4.1.5cu.748_B20211015. The issue resides in the recvSlaveUpgstatus function within the MQTT Service component, where manipulation of the argument "s" triggers the overflow. Classified under CWE-119 and CWE-120, it carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for remote exploitation.
Attackers with low privileges (PR:L) can exploit this vulnerability remotely over the network with low complexity and no user interaction required. By sending crafted input to the affected function, they can achieve high impacts on confidentiality, integrity, and availability, potentially leading to arbitrary code execution, data compromise, or device disruption on the targeted router.
References including VulDB entries and a GitHub repository provide details on the vulnerability, with the latter disclosing a proof-of-concept exploit. No vendor advisories or patches are mentioned in the available information, emphasizing the need for practitioners to isolate affected devices and monitor for exploitation attempts until firmware updates are confirmed. The public disclosure of the exploit increases the risk of active use by threat actors.
Details
- CWE(s)