CVE-2026-49196: Wi-Fi Device Blocking RCE Vulnerability

CVE-2026-49196 Overview

CVE-2026-49196 is a command injection vulnerability [CWE-77] in a Wi-Fi device blocking feature. The flaw stems from missing input sanitization on the MAC address field. Attackers can inject shell metacharacters into the MAC address parameter and execute arbitrary commands on the underlying operating system. Acer published a knowledge base article addressing the issue, indicating the affected functionality resides in an Acer product.

Critical Impact
Authenticated attackers can execute arbitrary shell commands on the affected device, leading to full compromise of confidentiality, integrity, and availability of the host system.

Affected Products

Acer device with Wi-Fi blocking management feature (refer to the Acer Knowledge Base Article for affected models and firmware versions)

Discovery Timeline

2026-05-29 - CVE-2026-49196 published to the National Vulnerability Database (NVD)
2026-05-29 - Last updated in NVD database

Technical Details for CVE-2026-49196

Vulnerability Analysis

The vulnerability resides in the Wi-Fi device blocking workflow. The feature accepts a MAC address from the user and passes it to an underlying system command without proper validation or escaping. Because the input flows into a shell context, an attacker can append shell metacharacters such as ;, |, &&, or backticks to break out of the intended argument and execute additional commands.

The Common Weakness Enumeration classifies this as [CWE-77]: Improper Neutralization of Special Elements used in a Command (Command Injection). Successful exploitation yields code execution under the privileges of the process handling the blocking operation, which on embedded management interfaces is typically elevated.

Root Cause

The root cause is missing input validation. The blocking feature expects a properly formatted MAC address such as aa:bb:cc:dd:ee:ff, but it does not enforce that format with a strict allowlist regular expression. Instead, the user-supplied string is concatenated directly into a shell command string and executed through a function such as system(), popen(), or an unescaped shell invocation.

Attack Vector

The attack requires network access to the affected management interface and authenticated, high-privilege access according to the CVSS vector. An attacker who reaches the Wi-Fi blocking configuration page submits a crafted MAC address containing shell metacharacters. The injected payload runs alongside the intended block command. No user interaction is needed for exploitation.

For exploitation specifics and the vendor's technical analysis, consult the Acer Knowledge Base Article. No public proof-of-concept code has been released, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2026-49196

Indicators of Compromise

Unexpected child processes spawned by the Wi-Fi management or web administration daemon
Outbound network connections from the device to attacker-controlled infrastructure shortly after a block operation
Modified configuration files, new cron jobs, or new user accounts on the affected device
HTTP requests to the Wi-Fi blocking endpoint containing shell metacharacters such as ;, |, $(), or backticks in the MAC address parameter

Detection Strategies

Inspect web server and application logs for MAC address fields that do not match the canonical ^([0-9A-Fa-f]{2}[:-]){5}[0-9A-Fa-f]{2}$ pattern
Monitor process execution telemetry on the device for shell interpreters launched as children of the management service
Alert on administrative API calls originating from unexpected source IP addresses or outside maintenance windows

Monitoring Recommendations

Forward device administrative logs to a centralized logging or SIEM platform for retention and correlation
Baseline normal process behavior of the Wi-Fi management daemon and alert on deviations
Review authentication logs for the management interface to detect credential compromise that would precede exploitation

How to Mitigate CVE-2026-49196

Immediate Actions Required

Apply the vendor firmware update referenced in the Acer Knowledge Base Article as soon as it is available for your device model
Restrict access to the device management interface to trusted administrative networks only
Rotate administrative credentials on affected devices to invalidate any access that may have been used to reach the vulnerable endpoint
Audit recent configuration changes and command execution logs for signs of exploitation

Patch Information

Acer has published guidance through its knowledge base. Administrators should review the Acer Knowledge Base Article for the list of affected products, fixed firmware versions, and update procedures. Apply the firmware update through the vendor-supported channel and verify the running version after the update.

Workarounds

Disable the Wi-Fi device blocking feature until the firmware update can be applied
Place the device management interface behind a VPN or restrict it to a dedicated management VLAN with strict access control lists
Limit administrative accounts to the minimum required and enforce strong, unique passwords combined with multi-factor authentication where supported

bash

# Example: restrict access to the management interface using iptables
# Replace 192.0.2.0/24 with your trusted administrative subnet
iptables -A INPUT -p tcp --dport 443 -s 192.0.2.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP