CVE-2025-7421
Published: 11 July 2025
Summary
CVE-2025-7421 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Tenda O3 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 18.4% 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
Requires validation of the 'mac' argument in the fromMacFilterModify function to prevent stack-based buffer overflows from malformed inputs.
Implements memory protections such as stack canaries and non-executable stacks to mitigate exploitation of the stack-based buffer overflow in the httpd component.
Directly addresses remediation of the identified buffer overflow flaw in Tenda O3V2 firmware version 1.0.0.12(3880) through patching or updates.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The stack-based buffer overflow in the httpd web component (/goform/operateMacFilter) of the public-facing Tenda O3V2 router enables remote exploitation for potential code execution, directly mapping to T1190: Exploit Public-Facing Application.
NVD Description
A vulnerability was found in Tenda O3V2 1.0.0.12(3880). It has been rated as critical. This issue affects the function fromMacFilterModify of the file /goform/operateMacFilter of the component httpd. The manipulation of the argument mac leads to stack-based buffer overflow. The…
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attack may be initiated remotely. The exploit has been disclosed to the public and may be used.
Deeper analysisAI
CVE-2025-7421 is a critical stack-based buffer overflow vulnerability (CWE-119, CWE-121) affecting the Tenda O3V2 device on firmware version 1.0.0.12(3880). The flaw exists in the fromMacFilterModify function of the /goform/operateMacFilter endpoint within the httpd component, where manipulation of the 'mac' argument triggers the overflow.
The vulnerability enables remote exploitation by an attacker with low privileges (PR:L) over the network (AV:N), requiring low attack complexity (AC:L) and no user interaction (UI:N). Successful exploitation can result in high impacts to confidentiality, integrity, and availability (C:H/I:H/A:H), as reflected in its CVSS v3.1 base score of 8.8.
Advisories and references, including GitHub repositories detailing a proof-of-concept and VulDB entries, confirm the exploit has been publicly disclosed and may be used by attackers. No specific patches or mitigations are detailed in the available information.
Details
- CWE(s)