CVE-2024-29972 — Nas326 Firmware
CRITICALCVE-2024-29972 is a critical-severity (CVSS 9.8) OS Command Injection vulnerability in zyxel nas326 firmware. 2 public exploit references exist, so weaponization risk is real. A fix is available — see the affected versions and patch details below.
** UNSUPPORTED WHEN ASSIGNED ** The command injection vulnerability in the CGI program "remote_help-cgi" in Zyxel NAS326 firmware versions before V5.21(AAZF.17)C0 and NAS542 firmware…
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-29972.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2024-29972 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).
Where this sits among everything scored
Of 395,308 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Counts from FIRST.org, log-scaled.
Description
** UNSUPPORTED WHEN ASSIGNED ** The command injection vulnerability in the CGI program "remote_help-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 some operating system (OS) commands by sending a crafted HTTP POST request.
Affected Products
nas326 firmwarezyxelnas542 firmwarezyxelResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Vendor / applianceDetect
Inventory every zyxel nas326 firmware deployment and check each version against the affected-products list above.
Fix
Apply the zyxel nas326 firmware security patch or hotfix for CVE-2024-29972 on the affected version, following the vendor advisory for your exact build.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
How to detect CVE-2024-29972
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2024-29972 -u https://target- Template
- Zyxel NAS326 Firmware < V5.21(AAZF.17)C0 - NsaRescueAngel Backdoor Account
- Severity
- critical
- Impact
- Attackers can use the backdoor account to gain unauthorized administrative access to the NAS device.
- Remediation
- Update Zyxel NAS326 firmware to a version that removes the backdoor account.
Template by ProjectDiscovery nuclei-templates (gy741), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2024-29972 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.