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CVE-2026-110958: The manipulation results in heap-based buffer overflow.

CVE-2026-110958 is rated critical with a CVSS v3.1 base score of 10.0. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

A vulnerability was found in Wavlink WN530HG4B M30HG4B_V260724. The impacted element is an unknown function of the file api.cgi. The manipulation results in heap-based buffer overflow. It is possible to launch the attack remotely. The exploit has been made public and could be used. Upgrading to version 2026-09-24-841a51c6d5_tclinux.bin is sufficient to resolve this issue. The affected component should be upgraded. The vendor confirms: "We confirm the finding, and it has already been addressed. In the current firmware the api=info&client=app handler no longer builds a shell command: the login script is now invoked through an argument vector (execvp) instead of system(), and the client address is length-limited and null-checked."

Severity breakdown

CVSS v3.1 10.0: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
Attack complexity: Low. No special conditions; the attack can be repeated reliably.
Privileges required: None. No account or prior access is needed.
User interaction: None. No action from any user is needed.
Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.

CWE-122: Heap-based Buffer Overflow

The product writes past the end of a buffer that was allocated on the heap.