CVE-2026-13581: EW-7478APC OS command injection

CISO Take

This is an OS command injection vulnerability in the web-based station-setup handler (formStaDrvSetup) of the Edimax EW-7478APC wireless router, where the rootAPmac parameter is passed unsanitized into a system call, letting a low-privileged authenticated attacker execute arbitrary commands as root over the network. It does not involve any AI/ML framework, model, or pipeline despite being tagged ai_tool in this feed — that classification appears to be a labeling artifact, and analysts should not treat it as an AI-stack risk. Exploitation likelihood is modest (EPSS 0.0116, ~top 37th percentile) and CISA's SSVC decision is TRACK* (routine monitoring, no urgent action), it is not in CISA KEV, and there is no Nuclei template, though a public exploit writeup already exists and the vendor was notified but never responded. Because Edimax has not acknowledged or patched this and the device is a low-cost consumer router, the pragmatic action is to identify any EW-7478APC units on the network (including ones sitting in front of edge/IoT or camera deployments), restrict management-interface access to trusted hosts only, disable remote administration, and plan replacement rather than wait for a fix. Watch for anomalous outbound connections or process spawning from the device's management IP as a detection signal for exploitation attempts against /goform/formStaDrvSetup.

Sources: vuldb.com EPSS CISA KEV

What is the risk?

Medium severity (CVSS 6.3, AV:N/AC:L/PR:L) — network-reachable and low complexity, but requires the attacker to already hold low-level privileges (e.g., valid low-priv session or LAN/adjacent access to the admin web UI), which narrows the population of exploitable-without-any-access scenarios. EPSS is low (0.0116, ~37th percentile) and CISA SSVC lands on TRACK*, indicating no evidence of active mass exploitation. A public exploit description exists, which raises opportunistic risk once any authenticated foothold (e.g., default/weak credentials) is obtained, but there's no KEV listing or scanner template, and the vendor has gone unresponsive, so no official patch timeline exists. Overall risk to AI/ML environments specifically is negligible — this is embedded router firmware, not an AI component.

How does the attack unfold?

Initial Access

Attacker obtains low-privileged access to the router's web admin interface (e.g., default/weak credentials or LAN access).

Exploitation

Attacker sends a crafted POST request to /goform/formStaDrvSetup with malicious shell metacharacters in the rootAPmac parameter, triggering OS command injection.

Impact

Attacker achieves root-level command execution on the router, enabling full device takeover and potential pivoting into the wider network, including any AI/IoT devices behind it.

Initial Access

Attacker obtains low-privileged access to the router's web admin interface (e.g., default/weak credentials or LAN access).

Exploitation

Attacker sends a crafted POST request to /goform/formStaDrvSetup with malicious shell metacharacters in the rootAPmac parameter, triggering OS command injection.

Impact

Attacker achieves root-level command execution on the router, enabling full device takeover and potential pivoting into the wider network, including any AI/IoT devices behind it.

What systems are affected?

Package	Ecosystem	Vulnerable Range	Patched
EW-7478APC	—	—	No patch

Do you use EW-7478APC? You're affected.

How severe is it?

CVSS 3.1

6.3 / 10

EPSS

2.0%

chance of exploitation in 30 days

Higher than 80% of all CVEs

Source: EPSS v3 — FIRST.org

Exploitation Status

Exploit Available

Exploitation: MEDIUM

Sophistication

Trivial

Exploitation Confidence

medium

○ CISA SSVC: Public PoC

Composite signal derived from CISA KEV, VulnCheck KEV, CISA SSVC, EPSS, Metasploit, Exploit-DB, trickest/cve, Nuclei templates, and inthewild.io exploitation reports.

What is the attack surface?

AV Network

AC Low

PR Low

UI None

S Unchanged

C Low

I Low

A Low

What should I do?

1 step

1) Inventory the network for EW-7478APC devices (firmware 1.04) and check whether they front any AI/IoT infrastructure. 2) Since the vendor has not responded and no patch exists, disable remote/WAN administration on the device and restrict LAN admin access to trusted management VLANs or specific IPs. 3) Change default/weak credentials immediately, since PR:L exploitation likely relies on obtaining a low-privilege session first. 4) Monitor router logs/traffic for unexpected POST requests to /goform/formStaDrvSetup or anomalous outbound connections from the device. 5) Treat this as an EOL/unsupported device and plan replacement with a vendor that maintains active security response, especially if it sits in front of any production or lab AI systems.

What does CISA's SSVC say?

Decision Track*

Exploitation poc

Automatable No

Technical Impact partial

Source: CISA Vulnrichment (SSVC v2.0). Decision based on the CISA Coordinator decision tree.

How is it classified?

Code Execution Framework

Which compliance frameworks are affected?

Compliance analysis pending. Sign in for full compliance mapping when available.

Frequently Asked Questions

What is CVE-2026-13581?

This is an OS command injection vulnerability in the web-based station-setup handler (formStaDrvSetup) of the Edimax EW-7478APC wireless router, where the rootAPmac parameter is passed unsanitized into a system call, letting a low-privileged authenticated attacker execute arbitrary commands as root over the network. It does not involve any AI/ML framework, model, or pipeline despite being tagged ai_tool in this feed — that classification appears to be a labeling artifact, and analysts should not treat it as an AI-stack risk. Exploitation likelihood is modest (EPSS 0.0116, ~top 37th percentile) and CISA's SSVC decision is TRACK* (routine monitoring, no urgent action), it is not in CISA KEV, and there is no Nuclei template, though a public exploit writeup already exists and the vendor was notified but never responded. Because Edimax has not acknowledged or patched this and the device is a low-cost consumer router, the pragmatic action is to identify any EW-7478APC units on the network (including ones sitting in front of edge/IoT or camera deployments), restrict management-interface access to trusted hosts only, disable remote administration, and plan replacement rather than wait for a fix. Watch for anomalous outbound connections or process spawning from the device's management IP as a detection signal for exploitation attempts against /goform/formStaDrvSetup.

Is CVE-2026-13581 actively exploited?

No confirmed active exploitation of CVE-2026-13581 has been reported, but organizations should still patch proactively.

How to fix CVE-2026-13581?

1) Inventory the network for EW-7478APC devices (firmware 1.04) and check whether they front any AI/IoT infrastructure. 2) Since the vendor has not responded and no patch exists, disable remote/WAN administration on the device and restrict LAN admin access to trusted management VLANs or specific IPs. 3) Change default/weak credentials immediately, since PR:L exploitation likely relies on obtaining a low-privilege session first. 4) Monitor router logs/traffic for unexpected POST requests to /goform/formStaDrvSetup or anomalous outbound connections from the device. 5) Treat this as an EOL/unsupported device and plan replacement with a vendor that maintains active security response, especially if it sits in front of any production or lab AI systems.

What is the CVSS score for CVE-2026-13581?

CVE-2026-13581 has a CVSS v3.1 base score of 6.3 (MEDIUM). The EPSS exploitation probability is 1.99%.

What are the technical details?

Original Advisory

A vulnerability was detected in Edimax EW-7478APC 1.04. This vulnerability affects the function formStaDrvSetup of the file /goform/formStaDrvSetup of the component POST Request Handler. The manipulation of the argument rootAPmac results in os command injection. The attack can be executed remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Exploitation Scenario

An attacker who has obtained low-privileged access to the router's web management interface — via default credentials, a leaked password, or LAN/adjacent-network access — sends a crafted HTTP POST request to /goform/formStaDrvSetup with shell metacharacters embedded in the rootAPmac parameter. The unsanitized value is passed to an OS command execution routine on the embedded Linux system, giving the attacker root-level command execution on the router. From there, the attacker can pivot within the local network, intercept or redirect traffic (including traffic to/from any AI/IoT devices behind the router), or use the compromised router as a persistent foothold, since the exploit technique is already publicly documented.

Weaknesses (CWE)

CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection') CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CWE-77 — Improper Neutralization of Special Elements used in a Command ('Command Injection'): The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.

[Architecture and Design] If at all possible, use library calls rather than external processes to recreate the desired functionality.
[Implementation] If possible, ensure that all external commands called from the program are statically created.

Source: MITRE CWE corpus.