CVE-2026-31027: totolink a3600r_firmware Classic Buffer Overflow

Vulnerability summary

CVE-2026-31027 is a critical (CVSS 9.8) Classic Buffer Overflow vulnerability in totolink a3600r_firmware. EPSS estimates a 1.59% chance of exploitation in the next 30 days, higher than 75.4% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 01-04-2026
   PublishedVulnerability first disclosed.
2. 01-04-2026
   Last modifiedVulnerability information updated.

Description

TOTOlink A3600R v5.9c.4959 contains a buffer overflow vulnerability in the setAppEasyWizardConfig interface of /lib/cste_modules/app.so. The vulnerability occurs because the rootSsid parameter is not properly validated for length, allowing remote attackers to trigger a buffer overflow, potentially leading to arbitrary code execution or denial of service.

• 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.