Cyber Posture

CVE-2024-39756

CriticalPublic PoC

Published: 14 January 2025

Published
14 January 2025
Modified
21 August 2025
KEV Added
Patch
CVSS Score 9.1 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0045 63.7th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2024-39756 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Wavlink Wl-Wn533A8 Firmware. Its CVSS base score is 9.1 (Critical).

Operationally, ranked in the top 36.3% 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-16 (Memory Protection).

Threat & Defense at a Glance

What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly prevents stack-based buffer overflow by validating the size and format of specially crafted HTTP request inputs to the adm.cgi rep_as_router() function.

prevent

Implements memory protections such as stack canaries, ASLR, and DEP to block exploitation of stack buffer overflows even with malformed inputs.

prevent

Requires timely remediation of the identified buffer overflow flaw through firmware patching or updates specific to Wavlink AC3000 M33A8.V5030.210505.

NVD Description

A buffer overflow vulnerability exists in the adm.cgi rep_as_router() functionality of Wavlink AC3000 M33A8.V5030.210505. A specially crafted HTTP request can lead to stack-based buffer overflow. An attacker can make an authenticated HTTP request to trigger this vulnerability.

Deeper analysisAI

A buffer overflow vulnerability, tracked as CVE-2024-39756 and published on 2025-01-14, affects the adm.cgi rep_as_router() functionality in Wavlink AC3000 routers running firmware version M33A8.V5030.210505. The issue stems from CWE-120 (Buffer Copy without Checking Size of Input), where a specially crafted HTTP request triggers a stack-based buffer overflow. This flaw has a CVSS v3.1 base score of 9.1 (AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H), indicating critical severity due to its potential for high confidentiality, integrity, and availability impacts with changed scope.

Exploitation requires an authenticated attacker with high privileges (PR:H) to send a malicious HTTP request to the vulnerable component over the network (AV:N) with low complexity (AC:L) and no user interaction (UI:N). Successful exploitation can lead to arbitrary code execution, enabling full compromise of the affected router, including potential data theft, modification of configurations, or denial of service.

Mitigation details are available in the Talos Intelligence advisory at https://talosintelligence.com/vulnerability_reports/TALOS-2024-2024. Security practitioners should consult this report for patch information, workarounds, or firmware updates specific to the Wavlink AC3000 device.

Details

CWE(s)

Affected Products

wavlink
wl-wn533a8 firmware
m33a8.v5030.210505

CVEs Like This One

CVE-2024-36290Same product: Wavlink Wl-Wn533A8
CVE-2024-37184Same product: Wavlink Wl-Wn533A8
CVE-2024-39770Same product: Wavlink Wl-Wn533A8
CVE-2024-39370Same product: Wavlink Wl-Wn533A8
CVE-2024-36272Same product: Wavlink Wl-Wn533A8
CVE-2024-39803Same product: Wavlink Wl-Wn533A8
CVE-2024-39299Same product: Wavlink Wl-Wn533A8
CVE-2024-39769Same product: Wavlink Wl-Wn533A8
CVE-2024-39768Same product: Wavlink Wl-Wn533A8
CVE-2024-39774Same product: Wavlink Wl-Wn533A8

References