CVE-2026-31027
Published: 01 April 2026
Summary
CVE-2026-31027 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Totolink A3600R Firmware. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 21.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly mandates information input validation mechanisms at entry points to check parameters like rootSsid for length, preventing the buffer overflow condition.
Implements memory protection such as address space layout randomization and data execution prevention to mitigate exploitation of buffer overflows even if validation fails.
Requires timely flaw remediation to identify and patch the specific buffer overflow vulnerability in the setAppEasyWizardConfig interface.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The vulnerability is a remotely exploitable buffer overflow in a public-facing web interface (setAppEasyWizardConfig) on a router firmware, enabling arbitrary code execution without authentication, directly mapping to Exploit Public-Facing Application (T1190).
NVD 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…
more
execution or denial of service.
Deeper analysisAI
CVE-2026-31027, published on 2026-04-01, is a buffer overflow vulnerability (CWE-120) in TOTOlink A3600R router firmware version v5.9c.4959. The flaw exists in the setAppEasyWizardConfig interface of the /lib/cste_modules/app.so library, where the rootSsid parameter is not properly validated for length, enabling a buffer overflow condition.
The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating critical severity. Remote attackers require no privileges or user interaction and can exploit it over the network with low attack complexity. Successful exploitation may lead to arbitrary code execution or denial of service on the targeted device.
Detailed technical analysis of the vulnerability is available in the referenced GitHub repository at https://github.com/SunnyYANGyaya/cuicuishark-sheep-fishIOT/blob/main/ToTolink/A3600R/rootSsid-setAppEasyWizardConfig.md. No vendor advisories or patches are mentioned in the provided information.
Details
- CWE(s)