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The Return to Snort: When Legacy Tools Outshine AI in Cyber Defense
At Cisco Live San Diego 2025, the spotlight fell not on bleeding-edge AI or machine learning models, but on the dependable resilience of traditional Snort rules. While the Security Operations Center (SOC) has leaned heavily on the Encrypted Visibility Engine (EVE) and SnortML in recent months, it was a seemingly ordinary Snort rule that triggered over 1,000 security events and led to one of the conferenceâs most critical discoveries. This unexpected pivot back to basics served as a powerful reminder: old-school tools still have serious value in todayâs sophisticated cybersecurity landscape.
As Ciscoâs Secure Firewall team kicked off their morning shift, they were immediately alerted to a massive surge in alertsâ1,395 to be exactâlinked to a single rule: âSERVER-WEBAPP Cisco DNA Center API default login attempt.â That volume of alerts raised questions. Was this a false positive storm, or was something genuinely dangerous unfolding within the network? A systematic investigation ensued, dissecting the issue across network, host, and event levels. The findings confirmed that real admin credentials were being transmitted in cleartextâa potentially hazardous situation, even though it was later found to be limited to a network segment inaccessible to general conference attendees.
This case highlighted the importance of proactive analysis, swift incident escalation, and the constant need to secure credentialsâeven in segmented zones. The real takeaway? Cybersecurity isnât always about chasing the latest tech. Sometimes, a basic rule written for a well-known vulnerability can still be your first and best line of defense.
Behind the Firewall: What Happened at Cisco Live 2025
The Initial Trigger: Over 1,000 Events from One Rule
The Secure Firewall teamâs shift began with a sudden flood of alerts tied to default login attempts via Cisco DNA Centerâs API. This high-volume trigger immediately flagged something worthy of deeper inspection. Traditional instincts kicked in: investigate thoroughly before assuming either benign misconfiguration or active exploitation.
Network-Wide Monitoring Yields Clarity
Monitoring efforts extended beyond just the main attendee wireless network. Analysts also kept tabs on zones like CiscoTV, which attracted a staggering 14 million viewers during the event, and critical meeting areas like the Marriott Hotel. All flagged events pointed to infrastructure IP spaceâmeaning this wasnât just background noise or casual user misbehavior.
Narrowing It Down: Host Patterns and Event Filtering
The SOC quickly noticed that the majority of these 1,395 alerts were tied to a single destination IP, and that nearly all traffic stemmed from one of three source IPs. Drilling down, two of those IPs exhibited unique behaviors: one issued a reboot command (potential DoS indicator), while the other attempted to access admin resources (possible privilege escalation). Base64-encoded credentials used in both cases were quickly decoded, revealing the use of default login pairsâexactly what the rule was designed to detect.
Verifying Real Threats: Distinguishing True from False Positives
The investigators reached a critical point: while they couldnât yet confirm if the DNA Center was involved or if the login attempts were malicious, they confirmed a true positive finding. Someone was indeed using default credentials over an unencrypted channel. Thatâs always risky, regardless of intent.
Incident Escalation: Action Before Full Clarity
Despite not having full situational awareness, the SOC team escalated the issue. They submitted an incident report summarizing findings and suggesting potential responses depending on whether the traffic was legitimate or hostile. Such proactive escalation is core to real-time cybersecurity defense, especially in fast-moving environments like global conferences.
Final Outcome: Segmentation Helped, But Risks Remain
The traffic was ultimately confirmed as legitimate, and the credentials were limited to a segmented, isolated zone. While this level of segmentation is an effective mitigation, the reliance on default credentials and lack of encryption still presented a security gap. The incident was logged as an early, high-impact finding and a learning opportunity ahead of upcoming events like Black Hat USA 2025.
What Undercode Say:
The Lasting Power of Simplicity in Cyber Defense
This case proves something many cybersecurity professionals often forget: simplicity scales. In an industry increasingly obsessed with AI-driven solutions and behavior-based analytics, it was a humble, traditional Snort rule that caught one of Cisco Live 2025âs most actionable threats. That speaks volumes about the continuing relevance of foundational security techniques.
Event Overload Doesnât Mean False Alarm
A rule that fires 1,000+ events in minutes often triggers alert fatigue or gets deprioritized. But here, the SOC didnât tune it outâthey dug in. Their ability to break the situation into smaller pieces (by source IP, destination IP, and encoded credential behavior) allowed them to detect real issues masked within the noise. This is a prime lesson in incident triage.
Detection Is Only as Good as Contextual Analysis
What elevated this finding wasnât just the ruleâit was the investigatorsâ approach. Combining network zones, host behavior, and packet-level analysis painted a full picture. By focusing on rare but revealing outliers (the two less active IPs), they uncovered the critical insight faster. Context remains king in incident response.
Base64 Is Not Security
This case again showed how widespread the misuse of Base64 continues to be. Encoding is not encryption, and any credentials passed in Base64 are essentially exposed. When combined with default usernames and passwords, this becomes a prime attack vector. Events like Cisco Live are perfect practice grounds for catching these oversights in real time.
Segmentation Is a Mitigation, Not a Solution
The argument that traffic was isolated in a non-public segment may soften the severity of the incident, but it doesnât eliminate the risk. Security by obscurityâor by network segmentationâis still fragile if credentials are exposed. Organizations must treat all credentials with the same urgency, regardless of network isolation.
Default Credentials Should Be Treated as Vulnerabilities
This case reaffirms a best practice: never leave default logins in place, even on test systems or restricted networks. They are the low-hanging fruit attackers love. The fact that Snort picked up on them means they were detectableâso itâs a risk, not a convenience.
Incident Response Is Often Imperfect, and Thatâs OK
The SOC acted without knowing everything. And thatâs exactly the point of proactive security. Waiting for full clarity before acting can cost valuable time. By escalating based on “either/or” logic, they made sure no window of vulnerability was left open.
Old Rules Can Detect New Problems
Finally, this incident serves as a perfect example of how legacy rule sets can still catch contemporary issues. Attack vectors evolve, but so do the environments they target. Pairing old detection methods with modern analytical techniques yields the best results.
đ Fact Checker Results:
â
True positive confirmed: Admin credentials in the clear were detected
â
Network segmentation helped, but risk was still actionable
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Detection was based on traditional Snort rules, not newer AI tools
đ Prediction:
Expect future SOC setups at conferences like Black Hat USA 2025 to tighten their focus on eliminating default credentials, even within segmented zones. We will likely see a return to hybrid detection strategies that blend machine learning tools with tried-and-true Snort rules. As AI-based systems continue evolving, legacy tools will still play a vital role in exposing basic but dangerous misconfigurations.
References:
Reported By: blogs.cisco.com
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