Description
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.
Affected products
totolink: a720r firmware; totolink: a720r; totolink: lr1200gb firmware; totolink: lr1200gb; totolink: nr1800x firmware; totolink: nr1800x
References2
- github.com/yifan20020708/SGTaint-0-day/blob/main/ToToLink/ToToL… ExploitThird Party Advisory
- www.totolink.net/ Product
Metrics
- CVSS 3.1
-
5.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - EPSS — exploit probability
- 0% percentile: 15 · as of 11 November 2026
- CWE
- CWE-121
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