CVE-2024-29974
Zyxel Nas326 Firmware ≤ 5.21\(aazf.17\)c0
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2024-29974 is a critical-severity Unrestricted Upload of File with Dangerous Type (CWE-434) vulnerability in Zyxel Nas326 Firmware. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 2% 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 SI-3 (Malicious Code Protection) and CM-7 (Least Functionality) — 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.
CVE-2024-29974 is a remote code execution vulnerability in the file_upload-cgi CGI program present in Zyxel NAS326 firmware versions prior to V5.21(AAZF.17)C0 and NAS542 firmware versions prior to V5.21(ABAG.14)C0. The flaw, assigned CWE-434, permits an unauthenticated attacker to upload a crafted configuration file that results in arbitrary code execution on the device. It carries a CVSS 3.1 score of 9.8 reflecting network-accessible attack complexity that is low with no required credentials or user interaction.
An unauthenticated remote attacker can exploit the issue over the network by sending a malicious configuration file to the vulnerable CGI endpoint, achieving full control over the affected NAS device including the ability to read, modify, or delete data and disrupt availability.
Zyxel’s security advisory and related analysis from Outpost24 state that the affected firmware versions should be updated to the corrected releases V5.21(AAZF.17)C0 for NAS326 and V5.21(ABAG.14)C0 for NAS542; the CVE entry itself is flagged as unsupported when assigned, indicating the devices are beyond the vendor’s support lifecycle.
The associated EPSS score has reached a peak of 0.4760 with a current value of 0.4371, indicating substantial and sustained exploitation interest following disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2024-26948
Vulnerability Data
** UNSUPPORTED WHEN ASSIGNED ** The remote code execution vulnerability in the CGI program “file_upload-cgi” in Zyxel NAS326 firmware versions before V5.21(AAZF.17)C0 and NAS542 firmware versions before V5.21(ABAG.14)C0 could allow an unauthenticated attacker to execute arbitrary code by uploading a…
more
crafted configuration file to a vulnerable device.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V5.1.1
Mitigating Controls (NIST 800-53 r5) AI
Malicious-code protection at entry points blocks dangerous file types from being accepted and executed.
Least functionality restricts the file types and automatic processing capabilities the system will accept.
Mobile-code controls define, authorize, and block unacceptable uploaded code before automatic processing 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.
Restricting execution of unauthorized software directly blocks dangerous uploaded files from running.
Hardened configuration baselines can enforce allowed file types and processing rules.
Secure development practices include input validation and file-type restrictions that prevent this weakness.
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.
Configuration and acceptance testing verify that file-upload handling enforces allowed types and does not permit dangerous content to be stored or executed.
Secure-coding guidelines and security testing explicitly address restrictions on allowed file types and upload handling, reducing the risk that dangerous file uploads are accepted without validation.
Mandated testing for malicious content and known vulnerabilities reduces the likelihood that an outsourced component will contain or accept dangerous file types that could later be uploaded or executed.
Application allow-listing and pre-use scanning of received files directly blocks the introduction of executable content that has not been vetted, eliminating the primary vector for unrestricted dangerous file uploads.