CVE-2026-31027
Memory Safety in Totolink A3600R Firmware 5.9c.4959
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
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 Exploitation for Privilege Escalation (T1068); ranked at the 45th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
TOTOlink A3600R v5.9c.4959 contains a buffer overflow vulnerability in the setAppEasyWizardConfig interface of /lib/cste_modules/app.so. The flaw stems from missing length validation on the rootSsid parameter and is tracked as CWE-120 with a CVSS 3.1 score of 9.8.
Remote unauthenticated attackers can send a crafted request over the network to overflow the buffer, enabling arbitrary code execution or denial of service. The single available reference is a technical write-up hosted on GitHub that documents the parameter handling issue but provides no vendor advisory or patch information. The associated EPSS score remains flat at 0.0120 with no material increase after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-17913
Vulnerability Data
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.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V5.2.1
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and analysis can find missing size checks before deployment.
Input validation directly enforces size checks before buffer copies.
Engineering principles require bounds checking and safe buffer handling in design.
Memory protection limits the impact of an overflow once it occurs.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure development practices directly enforce bounds checking and input validation that prevent classic buffer overflows.
Vulnerability identification processes such as code review or scanning detect classic buffer overflows before exploitation.
Routine patching replaces vulnerable code containing unchecked buffer copies with corrected versions.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Secure coding directly requires bounds-checked memory operations, addressing the root cause of CWE-120.
Security testing in development and acceptance can detect buffer overflows through fuzzing and static analysis, though it does not prevent them at the source.
Secure development life cycle mandates processes that can include input validation and bounds checking to prevent buffer overflows.
Application security requirements can specify input-size validation and safe buffer handling to mitigate classic buffer overflows.
Secure system architecture and engineering principles promote defensive coding patterns that reduce the likelihood of unchecked buffer copies.