Cyber Resilience

CVE-2024-39786

CriticalPublic PoC

Published: 14 January 2025

Published
14 January 2025
Modified
03 November 2025
KEV Added
Patch
CVSS Score v3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0028 51.4th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2024-39786 is a critical-severity Path Traversal (CWE-22) vulnerability in Wavlink Wl-Wn533A8 Firmware. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 48.6% 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-2 (Flaw Remediation).

Deeper analysis

Multiple directory traversal vulnerabilities exist in the nas.cgi add_dir() functionality of the Wavlink AC3000 router running firmware version M33A8.V5030.210505. These flaws, including one specifically within the `adddir_name` POST parameter, allow a specially crafted HTTP request to bypass permissions. The vulnerabilities are classified under CWE-22 and carry 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 network accessibility, low attack complexity, and high impacts across confidentiality, integrity, and availability with changed scope.

An authenticated attacker with high privileges (PR:H) can exploit these vulnerabilities by sending a malicious HTTP request to the affected nas.cgi endpoint. This triggers directory traversal, enabling permission bypass that grants unauthorized access to sensitive directories and files. Successful exploitation could allow the attacker to read, modify, or delete critical data, potentially leading to full compromise of the device given the high-impact CVSS metrics.

Mitigation details are outlined in the Cisco Talos Intelligence advisory at https://talosintelligence.com/vulnerability_reports/TALOS-2024-2057, which provides technical analysis and recommendations for addressing TALOS-2024-2057.

EU & UK References

Vulnerability details

Multiple directory traversal vulnerabilities exist in the nas.cgi add_dir() functionality of Wavlink AC3000 M33A8.V5030.210505. A specially crafted HTTP request can lead to permission bypass. An attacker can make an authenticated HTTP request to trigger these vulnerabilities.A directory traversal vulnerability exists…

more

within the `adddir_name` POST parameter.

CWE(s)

Related Threats

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.
Why these techniques?

Directory traversal in public-facing nas.cgi web endpoint directly enables remote exploitation of the router's application interface for unauthorized file access.

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

CVEs Like This One

CVE-2024-39787Same product: Wavlink Wl-Wn533A8
CVE-2024-39604Same product: Wavlink Wl-Wn533A8
CVE-2024-39803Same product: Wavlink Wl-Wn533A8
CVE-2024-37184Same product: Wavlink Wl-Wn533A8
CVE-2024-34166Same product: Wavlink Wl-Wn533A8
CVE-2024-39790Same product: Wavlink Wl-Wn533A8
CVE-2024-39768Same product: Wavlink Wl-Wn533A8
CVE-2024-36290Same product: Wavlink Wl-Wn533A8
CVE-2024-39603Same product: Wavlink Wl-Wn533A8
CVE-2024-39794Same product: Wavlink Wl-Wn533A8

Affected Assets

wavlink
wl-wn533a8 firmware
m33a8.v5030.210505

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly prevents directory traversal vulnerabilities by validating inputs like the adddir_name POST parameter against traversal sequences such as '../' in nas.cgi.

prevent

Remediates the specific flaw in the nas.cgi add_dir() function through timely firmware patching to eliminate the permission bypass.

prevent

Enforces access control policies to restrict unauthorized file and directory access even if partial path traversal occurs.

References