The Black Duck research team recently disclosed findings related to a Broadcom Wi-Fi chipset commonly used across enterprise, consumer, and embedded routers.
During testing, the CyRC team found Defensics anomaly test cases that caused the network to stop working until the router was manually reset. This vulnerability allows an attacker to make the access point unresponsive to all clients and terminate any ongoing client connections.
If data transmission to subsequent systems is ongoing, the data may become corrupted or, at minimum, the transmission will be interrupted. Because this attack requires no authentication and works regardless of encryption settings, it represents a low-barrier, high-impact denial-of-service vector.
The Broadcom Wi-Fi vulnerability is a reminder that security isn’t just about strong passwords or encryption—it’s about building resilience at every layer. Experts around the industry also offered their insights on the bigger-picture issues of this vulnerability.
Ben Ronallo, Principal Cybersecurity Engineer at Black Duck
"Implementation-level flaws in protocols, such as 802.11, are often more difficult to detect than cryptographic weaknesses. Cryptographic weaknesses are easier to find because there are often only software dependencies.
"A researcher can build the code with breakpoints and watch the memory as the software executes. However, in a scenario like this, there are also hardware dependencies required for testing. The access point and a compatible antenna are required to perform this type of testing. Further complicating things, the access point firmware is almost always closed source which makes introspection much more difficult.
"Remediation of vulnerabilities in hardware/firmware are always slower due to the downstream effects needing to be fully tested. That testing requires time from multiple, independent parties to ensure any changes don’t introduce additional bugs into their products.
"In the software world, the commonly cited deadline is 90 days but for hardware/firmware its closer to 180+ days. The sooner all relevant parties are engaged, the better. In this scenario, testing was carried out against an ASUS access point, but the vulnerability existed in a Broadcom chipset. This nuance won’t be obvious to most/all researchers.
"There are a few, key takeaways from this research for both security teams. If you’re building networking, segment your networks to prevent a direct path to your critical systems. Audit for end of life/support systems (e.g., access points) and replace them when possible. If that’s not possible, lock them down, have redundant logging in place, and monitor network edges with intrusion detection/prevention, and patch your systems."
James Maude, Field CTO at BeyondTrust
"This Black Duck CyRC research is very reminiscent of early days of Wi-Fi adoption where de-auth and denial-of-service attacks against wireless networks were very common. Given the huge dependence on connectivity and ever increasing numbers of IoT and smart devices, the impacts could be significant.
"This has the potential to open the door to evil twin attacks where the real access point is knocked offline and a rogue one with the same name and password replaces it. While the risks of network traffic interception have decreased thanks to the widespread adoption of HTTPS encryption, there is still the risk of captive portals.
"When the user tries to restore their network connection, they are presented with a captive phishing portal requesting their personal or corporate credentials - leading to identity compromise."
Saumitra Das, Vice President of Engineering at Qualys
"This attack is both easy to execute and highly disruptive, underscoring that even mature and widely deployed network technologies can still yield new and serious attack vectors.
"Because the attack can be launched by an unauthenticated client, encryption alone offers little protection. This is precisely why fuzz testing plays a critical role in validating protocol-stack implementations such as Wi-Fi.
"These realities highlight why security teams must start with strong visibility into their environments through accurate asset inventory and continuous scanning, combined with the ability to tag assets by business criticality. It is not enough to know that access points are vulnerable; teams must understand where they are deployed and how much they matter to the business.
"An access point supporting a small innovation lab carries very different risk than one embedded in a core manufacturing or logistics operation. By tagging assets with business context, security teams can prioritize patching in an organized and risk-driven way.
"The goal is not simply to remediate vulnerabilities, but to reduce business risk. For example, access points on a factory floor that could halt operations during a denial-of-service attack should be addressed before those in an office environment, where users may have alternative connectivity such as wired or cellular networks."
Randolph Barr, CISO at Cequence Security
"At first glance, this vulnerability seems scary because it lets one unverified wireless frame keep disrupting a 5 GHz network until someone has to step in. However, organizations should know that the main risk isn't simply the outage itself; it's what long-term instability allows and how deeply it affects how the organization runs.
"Based on what I've seen, problems like this don't usually stay limited to 'IT issues.' Most offices today use wireless connections more than traditional ones. This problem is why wireless dependability and business continuity are important.
"Attackers don't have to completely take over a device to do damage if they can keep breaking the connection without authentication. They can stop sales conversations, mess up communications between executives, affect support operations, and make employees use risky workarounds like personal hotspots or unmanaged networks. That's generally where secondary security vulnerabilities start to show themselves.
"This flaw doesn't mean that someone can immediately take over the router or spy on it, but it does show that the wireless control plane's trust limits have broken down. This kind of issue is an area that many companies think is safe just because it is encrypted.
"IT teams should implement three practical procedures.
- Prioritize firmware updates from vendors and confirm that wireless infrastructure is running patched chipset software.
- Don't just think of recurring wireless problems, mass client disconnects, or unexplained radio failures as signs of environmental interference; they could also be signs of security problems.
- Plan for how people will act during outages by minimizing risky fallback options and making sure employees know exactly what to do when connectivity is lost.
"On a larger scale, businesses should see this as a warning that security is built on availability. When availability fails, confidentiality and integrity often follow. It's not about making people scared to deal with these risks; it's about realizing that stable wireless infrastructure is essential for running a business today, and attackers know it."
