Buffer overflow in Totolink A720r
CVE-2025-60686
A local stack-based buffer overflow vulnerability exists in the infostat.cgi and cstecgi.cgi binaries of ToToLink routers (A720R V4.1.5cu.614_B20230630, LR1200GB V9.1.0u.6619_B20230130, and NR1800X V9.1.0u.6681_B20230703). Both programs parse the contents of /proc/net/arp using sscanf() with "%s" format specifiers into fixed-size stack buffers without length validation. Specifically, one function writes user-controlled data into a single-byte buffer, and the other into adjacent small arrays without bounds checking. An attacker who controls the contents of /proc/net/arp can trigger memory corruption, leading to denial of service or potential arbitrary code execution.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L.
EPSS exploit prediction
EPSS: 0.002 (11.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 11th percentile — 11.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Totolink A720r
- Totolink A720r Firmware — versions 4.1.5cu.614_b20230630
- Totolink Lr1200gb
- Totolink Lr1200gb Firmware — versions 9.1.0u.6619_b20230130
- Totolink Nr1800x
- Totolink Nr1800x Firmware — versions 9.1.0u.6681_b20230703
Weakness classification (CWE)
References
- totolink.com (Broken Link)
- www.totolink.net/ (Product)
- github.com/yifan20020708/SGTaint-0-day/blob/main/ToToLink/ToToLink-A720R/CVE-20… (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2025-60686?
- CVE-2025-60686 is a medium-severity vulnerability in Totolink A720r, classified under Stack-based Buffer Overflow. CVSS score: 5.1/10. Published 2025-11-13.
- How severe is CVE-2025-60686?
- Medium severity. CVSS v3 base score is 5.1 out of 10.