Patchfirst
CVE-2023-27992 KEV Critical · 9.8 EPSS 82.3%

Zyxel Multiple NAS Devices Command Injection Vulnerability

Zyxel · Multiple Network-Attached Storage (NAS) Devices

Summary

A pre-authentication command injection flaw affects Zyxel NAS326, NAS540, and NAS542 network-attached storage devices in firmware versions prior to the fixed releases. An unauthenticated attacker can run some operating system commands on the device remotely by sending a crafted HTTP request, with no credentials or user interaction required.

Official description · NVD

The pre-authentication command injection vulnerability in the Zyxel NAS326 firmware versions prior to V5.21(AAZF.14)C0, NAS540 firmware versions prior to V5.21(AATB.11)C0, and NAS542 firmware versions prior to V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands remotely by sending a crafted HTTP request.

Breakdown
61.8 / 100
Exploited
Yes, in CISA KEV
Reports
0
Tactics
2/15

How an attack unfolds

Based on mappings. Select a step to see the evidence.
  1. How attackers get in

  2. What they do

First seen exploited 4 days after disclosure.

  1. Disclosedday 0
  2. First seen exploitedVulnCheck KEV evidenceAdded to CISA KEVEU database agrees+4 days

CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.

techniques

2 , grouped by in kill-chain order, 2 cited passages 2

Initial AccessTA0001

Exploit Public-Facing Application T1190 Medium
AI mapping from the description · how it is exploited

Unauthenticated remote exploit against network-facing service

pre-authentication command injection vulnerability
From the official description (NVD) Original (opens in a new tab) ↗

ExecutionTA0002

Command and Scripting Interpreter T1059 Medium
AI mapping from the description · primary impact

Direct OS command execution resulting from injection

could allow an unauthenticated attacker to execute some operating system (OS) commands remotely
From the official description (NVD) Original (opens in a new tab) ↗

Detection

0 rules for this CVE · 244 general rules for its techniques

Rules for this CVE

0 that reference CVE-2023-27992 directly.

CVE-specific rules are not available in this build. Search SigmaHQ ↗

Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.

What security researchers reported

Not named in any threat report yet

References

2 links, grouped by NVD tag (1 duplicate merged)
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