CVE-2026-19844: totolink a800r_firmware

Vulnerability summary

CVE-2026-19844 is a high (CVSS 9.0) vulnerability in totolink a800r_firmware. EPSS estimates a 0.85% chance of exploitation in the next 30 days, higher than 57.8% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 14-08-2026
   PublishedVulnerability first disclosed.
2. 18-08-2026
   Last modifiedVulnerability information updated.

Description

A vulnerability was found in TOTOLINK A800R 4.1.2cu.5137_B20200730. The impacted element is the function setRadvdCfg of the file /cgi-bin/cstecgi.cgi of the component ipv6.so. Performing a manipulation of the argument radvdinterfacename results in stack-based buffer overflow. It is possible to initiate the attack remotely. The exploit has been made public and could be used.

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
• CWE-121Stack-based Buffer OverflowA stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).