CVE-2026-8137: Totolink X5000R formDdns sub_458E40 buffer overflow

Vulnerability summary

CVE-2026-8137 is a high (CVSS 9.0) vulnerability in totolink x5000r_firmware. EPSS estimates a 0.79% chance of exploitation in the next 30 days, higher than 55.8% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 08-05-2026
   PublishedVulnerability first disclosed.
2. 08-05-2026
   Last modifiedVulnerability information updated.

Description

A vulnerability has been found in Totolink X5000R 9.1.0u.6369_B20230113. This vulnerability affects the function sub_458E40 of the file /boafrm/formDdns. The manipulation of the argument submit-url leads to buffer overflow. Remote exploitation of the attack is possible. The exploit has been disclosed to the public and may 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-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.