Cyber Posture

CVE-2026-5613

HighPublic PoC

Published: 06 April 2026

Published
06 April 2026
Modified
30 April 2026
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0011 28.5th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

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.

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly validates the 'webpage' argument in the formReboot function to prevent stack-based buffer overflow from malformed or oversized inputs.

prevent

Implements memory safeguards like bounds checking, stack canaries, and non-executable memory to protect against exploitation of the stack-based buffer overflow.

prevent

Requires timely identification, testing, and installation of patches or mitigations for known flaws like this unpatched buffer overflow vulnerability.

Security SummaryAI

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)

Affected Products

belkin
f9k1015 firmware
1.00.10

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
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.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

References