The NIST SP 800-61 Computer Security Incident Handling Guide defines a four-phase incident response lifecycle that applies directly to WiFi security incidents:
- Detection & Analysis: Identifying that an incident has occurred, determining its scope, and understanding what systems and data are involved
- Containment, Eradication & Recovery: Isolating affected systems, removing the attacker's access, and restoring normal operations
- Post-Incident Activity: Conducting a lessons-learned review, updating documentation, and improving defenses based on what was learned
Preparation is the foundation that makes all three phases effective. Before an incident occurs, your organization needs an incident response plan, trained personnel, communication channels, and tooling in place.
Pre-Incident Preparation Checklist- Documented incident response plan with WiFi-specific sections
- Designated incident response team with clear roles and escalation paths
- Contact list for external resources (law enforcement, legal counsel, IR firm, ISP)
- Network diagrams showing all WiFi access points, VLANs, and network segments
- Known-good baseline of normal WiFi traffic and AP inventory
- Forensic imaging and packet capture tooling ready to deploy
- Legal authorization for incident response activities documented
Early detection of a WiFi incident is critical. The longer an attacker remains undetected on the network, the more time they have to establish persistence, move laterally, and exfiltrate data. Here are the indicators that a WiFi compromise may be in progress or has occurred.
Network-Level Indicators- Unknown access points appearing on the RF spectrum: A WIDS or wireless site survey identifies a BSSID/ESSID that is not in the organization's known-good inventory. This is one of the clearest indicators of a rogue AP.
- Unusual outbound traffic from network devices: A surveillance camera, IoT sensor, or access point that suddenly starts beaconing to an external IP address at unusual hours may be compromised.
- Wireless client authentication anomalies: The same user account authenticating from multiple APs simultaneously, from APs in different physical locations within a short time, or at unusual hours.
- Unexpected ARP traffic: ARP spoofing (detected via ARPwatch or NAC alerts) on a WiFi VLAN indicates an attacker is attempting man-in-the-middle positioning.
- DNS anomalies: Devices on the WiFi network making DNS queries to unfamiliar DNS servers, or DNS query patterns that indicate a DNS hijacking attack is in progress.
- Unexpected certificate prompts: An employee's laptop prompts them to accept a new TLS certificate for a corporate resource. This can indicate an attacker is attempting to deploy a certificate to establish a MITM position.
- VPN connection failures or unusual VPN behavior: The VPN connects but routes traffic to unexpected destinations, or the VPN client shows a different external IP address than expected.
- New or unexpected software on endpoints: An employee's device suddenly has new processes, scheduled tasks, or registry entries that correspond to a reverse shell or remote access tool.
- Session hijacking indicators: A user is unexpectedly logged out of corporate applications, or sessions that should be persistent are being reset.
# Zeek â detecting potential DNS hijacking on the network $ # Look for DNS queries to unusual TLDs or suspicious query lengths $ zeek-cut -d $'\t' query answers < dns.log | awk '{print $1}' | sort | uniq -c | sort -rn | head -20 [Review top queried domains â look for suspicious domains not in normal usage] $ # Detect devices making DNS queries to non-corporate DNS servers $ # (legitimate clients should only query your corporate DNS servers) $ grep -v "10.10.10.1\|10.10.10.2" dns.log | grep "query" [Any hits indicate DNS queries bypassing the corporate DNS server â investigate] $ # Look for very long DNS queries (potential of DNS tunneling) $ awk '{ if(length($query) > 100) print $1, length($query), $query }' dns.log [Long subdomain strings inside DNS queries can indicate DNS tunneling]