CVE-2025-60685: a720r Stack Overflow — Exploit

Description

A stack buffer overflow exists in the ToToLink A720R Router firmware V4.1.5cu.614_B20230630 within the sysconf binary (sub_401EE0 function). The binary reads the /proc/stat file using fgets() into a local buffer and subsequently parses the line using sscanf() into a single-byte variable with the %s format specifier. Maliciously crafted /proc/stat content can overwrite adjacent stack memory, potentially allowing an attacker with filesystem write privileges to execute arbitrary code on the device.

Is your site exposed to CVE-2025-60685?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L

Weakness Type (CWE)

CWE-121 CWE-121

Affected Products

Vendor	Product	Versions
totolink	a720r_firmware	All
totolink	a720r	All

References

Exploits

https://github.com/yifan20020708/SGTaint-0-day/blob/main/ToToLink/ToToLink-A720R/CVE-2025-60685.md

Other References

http://totolink.com https://www.totolink.net/

Frequently Asked Questions

What is CVE-2025-60685? +

A stack buffer overflow exists in the ToToLink A720R Router firmware V4.1.5cu.614_B20230630 within the sysconf binary (sub_401EE0 function). The binary reads the /proc/stat file using fgets() into a local buffer and subsequently parses the line using sscanf() into a single-byte variable with the %s format specifier. Maliciously crafted /proc/stat content can overwrite adjacent stack memory, potentially allowing an attacker with filesystem write privileges to execute arbitrary code on the device. It has a CVSS v3.1 base score of 5.1 (MEDIUM).

How severe is CVE-2025-60685? +

CVE-2025-60685 has a CVSS v3.1 score of 5.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-60685? +

CVE-2025-60685 affects products from totolink, specifically: a720r, a720r_firmware. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-60685? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-6239

A stack‑based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF CreateUsers service, where the device fails to …

CVE-2026-8356

LibreOffice can import presentations in the legacy binary PPT format. A stack buffer overflow existed when importing a colour-replacement record. …

CVE-2026-40489

editorconfig-core-c is an EditorConfig core library for use by plugins supporting EditorConfig parsing. Versions up to and including 0.12.10 have …

CVE-2025-26382

Under certain circumstances the iSTAR Configuration Utility (ICU) tool could have a buffer overflow issue

CVE-2025-1533

A stack buffer overflow has been identified in the AsIO3.sys driver. This vulnerability can be triggered by input manipulation, may …

CVE-2025-3916

CWE-121: Stack-based Buffer Overflow vulnerability exists that could cause local attackers being able to exploit these issues to potentially execute …

CVE-2025-60685