Vulnerability report

Active exploitation observed Confirmed confidence Not in CISA KEV

CVE-2024-29972

NAS326 firmware Command Injection

Zyxel / NAS326 firmware · affected before v5.21\(aazf.17\)co

Watch CVE-2024-29972 Browse KEV feed
Severity
CVSS 9.8 · Critical
Confidence
Confirmed
Exploit status
Observed in sensors
EPSS
89.3%
First observed
12 Jun 2026
Last observed
02 Oct 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2024-29972 is an unauthenticated vulnerability affecting Zyxel NAS326 firmware, NAS542 firmware. ** UNSUPPORTED WHEN ASSIGNED ** The command injection vulnerability in the CGI program "remote_help-cgi" in Zyxel...

Is it exploited?

Yes. Previdian sensors observed exploitation attempts with confirmed confidence. Also confirmed by third-party sources.

Who is affected?

Zyxel / NAS326 firmware affected before v5.21\(aazf.17\)co.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

NAS326 firmware Command Injection

** 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.

zyxel Affected
nas326_firmware
Before v5.21\(aazf.17\)co
zyxel Affected
nas542_firmware
Before 5.21\(abag.14\)co
Zyxel Affected
NAS326 firmware
Before V5.21(AAZF.17)C0
Zyxel Affected
NAS542 firmware
Before V5.21(ABAG.14)C0
View vendor advisory (opens in new tab)
Published
04 Jun 2024
Exploited Since
12 Jun 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

edge nuclei_scanner

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

The Shadowserver

Recorded 13 Jul 2026

Previdian independently recorded this as exploited after first seeing it in honeypot sensors.

Active exploitation observed

Previdian sensor

First observed 12 Jun 2026

Previdian first observed exploitation attempts targeting this vulnerability in our honeypot sensors.

Proof of concept available

GitHub

Recorded 30 Jun 2024

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
The Shadowserver First 2026-07-13 00:00 UTC
Previdian Sensors 2026-07-15 07:39 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

First-party evidence of exploitation activity

Previdian sensors recorded exploitation attempts targeting this vulnerability. The cards and chart show volume, unique attackers, and daily activity.

14

Attempts observed

9

Unique attacker IPs

8

Attacker countries

BG · CH · HK · JP · NL · TM · US · YE

9

Sensors observed

CVE-2024-29972 exploitation attempts over the last 91 days

Daily events observed by Previdian sensors

Updated 17 Oct 2026

2
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19 Jul 7 Aug 26 Aug 14 Sep 17 Oct

First observed 12 Jun 2026 · Last observed 02 Oct 2026

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
1
8
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

Learn about Pro API access

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2024/CVE-2024-29972.yaml 25 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

9.8 Critical

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

89.3%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') CWE-78

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Zyxel NAS326 Firmware < V5.21(AAZF.17)C0 - NsaRescueAngel Backdoor Account

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 00:00 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  2. 14:20 UTC

    Public PoC available

    Public proof-of-concept code published

  3. 00:33 UTC

    Indicators of compromise added (15)

    Indicators of compromise recorded

  4. 00:33 UTC

    Observed by Previdian sensors

    Evidence-backed exploitation signal

  5. 00:00 UTC

    Nuclei template available

    Scanner coverage available

  6. 01:24 UTC

    CVE published

    Vulnerability disclosed publicly

  7. 08:49 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2024-29972

Sample API response 
{
  "cve_id": "CVE-2024-29972",
  "confidence": "Confirmed",
  "cvss_score": 9.8,
  "cvss_estimated": false,
  "epss_score": 0.89326,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 14, "sensors": 9 }
}