Cyber Resilience

CVE-2024-39802

Memory Safety in Wavlink Wl-Wn533A8 Firmware m33a8.v5030.210505

Public PoCMemory Safety
Published
14 January 2025
Modified
03 November 2025
CVSS Score v3.1 9.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0088 56th percentile
Risk Priority 60 floored blend · peak EPSS

Summary

CVE-2024-39802 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Wavlink Wl-Wn533A8 Firmware. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 44% 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 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.

Multiple buffer overflow vulnerabilities, including stack-based ones, affect the qos.cgi qos_settings() functionality in the Wavlink AC3000 router firmware version M33A8.V5030.210505. These flaws arise from insufficient input validation, particularly in the qos_dat POST parameter, allowing a specially crafted HTTP request to overflow buffers and potentially corrupt the stack.

An attacker with high privileges (PR:H), such as an authenticated administrative user, can exploit these vulnerabilities remotely over the network (AV:N) with low complexity (AC:L) and no user interaction (UI:N). Exploitation triggers a scope change (S:C), enabling high confidentiality, integrity, and availability impacts (C:H/I:H/A:H), as reflected in the CVSS v3.1 base score of 9.1. The issues stem from CWE-120 (buffer copy without checking size of input).

Mitigation guidance and further technical details are available in the Talos Intelligence advisory at https://talosintelligence.com/vulnerability_reports/TALOS-2024-2049.

EU & UK References

Vulnerability Data

Multiple buffer overflow vulnerabilities exist in the qos.cgi qos_settings() 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 these vulnerabilities.A buffer overflow vulnerability…

more

exists in the `qos_dat` POST parameter.

CWE(s)
CWE-120

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
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.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-39803Same product: Wavlink Wl-Wn533A8
CVE-2024-39358Same product: Wavlink Wl-Wn533A8
CVE-2024-37357Same product: Wavlink Wl-Wn533A8
CVE-2024-39768Same product: Wavlink Wl-Wn533A8
CVE-2024-36272Same product: Wavlink Wl-Wn533A8
CVE-2024-39774Same product: Wavlink Wl-Wn533A8
CVE-2024-39770Same product: Wavlink Wl-Wn533A8
CVE-2024-39299Same product: Wavlink Wl-Wn533A8
CVE-2024-37184Same product: Wavlink Wl-Wn533A8
CVE-2024-39370Same product: Wavlink Wl-Wn533A8

Affected Assets

wavlink
wl-wn533a8 firmware
m33a8.v5030.210505

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V5.2.1

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and analysis can find missing size checks before deployment.

SI-10 Information Input Validation good match

Input validation directly enforces size checks before buffer copies.

SA-8 Security and Privacy Engineering Principles partial match

Engineering principles require bounds checking and safe buffer handling in design.

SI-16 Memory Protection partial match

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.

PR.PS-06 mostly match
prevents

Secure development practices directly enforce bounds checking and input validation that prevent classic buffer overflows.

ID.RA-01 partial match
prevents

Vulnerability identification processes such as code review or scanning detect classic buffer overflows before exploitation.

PR.PS-02 partial match
prevents

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.

A.8.28 Secure coding mostly match
prevents

Secure coding directly requires bounds-checked memory operations, addressing the root cause of CWE-120.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development and acceptance can detect buffer overflows through fuzzing and static analysis, though it does not prevent them at the source.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates processes that can include input validation and bounds checking to prevent buffer overflows.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify input-size validation and safe buffer handling to mitigate classic buffer overflows.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure system architecture and engineering principles promote defensive coding patterns that reduce the likelihood of unchecked buffer copies.

References