CVE-2026-5613
Published: 06 April 2026
Summary
CVE-2026-5613 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Belkin F9K1015 Firmware. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 28.5th 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 are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly validates the 'webpage' argument in the formReboot function to prevent stack-based buffer overflow from malformed or oversized inputs.
Implements memory safeguards like bounds checking, stack canaries, and non-executable memory to protect against exploitation of the stack-based buffer overflow.
Requires timely identification, testing, and installation of patches or mitigations for known flaws like this unpatched buffer overflow vulnerability.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Stack-based buffer overflow in router web form (/goform/formReboot) enables remote authenticated low-priv RCE, directly mapping to public-facing app exploitation and privilege escalation via memory corruption.
NVD Description
A vulnerability was identified in Belkin F9K1015 1.00.10. This issue affects the function formReboot of the file /goform/formReboot. The manipulation of the argument webpage leads to stack-based buffer overflow. The attack may be initiated remotely. The exploit is publicly available…
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and might be used. The vendor was contacted early about this disclosure but did not respond in any way.
Deeper analysisAI
CVE-2026-5613 is a stack-based buffer overflow vulnerability affecting the Belkin F9K1015 router on firmware version 1.00.10. The flaw exists in the formReboot function of the /goform/formReboot file, where manipulation of the "webpage" argument triggers the overflow. Published on 2026-04-06, it carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) and is associated with CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-121 (Stack-based Buffer Overflow).
The vulnerability enables remote exploitation by an attacker with low privileges (PR:L), such as an authenticated user on the network. Attackers can send crafted requests to the affected endpoint, leading to high-impact consequences including unauthorized data access (C:H), system modification (I:H), and denial of service (A:H), potentially resulting in remote code execution.
VulDB advisories document the issue but note that the vendor was contacted early for disclosure and provided no response, with no patches or mitigations released. Key references include a GitHub repository hosting a public exploit at https://github.com/Litengzheng/vuldb_new/blob/main/Belkin%20F9K1015/vul_10/README.md and VulDB entries at https://vuldb.com/vuln/355404.
A public exploit is available and might be used in attacks, though no confirmed real-world exploitation has been reported in the provided details.
Details
- CWE(s)