The Breach We Should Have Seen Coming
When the FBI and CISA confirmed in late 2024 that Chinese state-sponsored actors had compromised at least nine major US telecommunications carriers through what they called Salt Typhoon, the reaction split into two camps. One side expressed shock that something of this scale could happen. The other side, the people who actually build and operate these networks, mostly shrugged and asked why it took so long to detect.
That second group had seen this coming for years. Every senior network engineer I know has been operating on the assumption that legacy telecom infrastructure was compromised the moment someone with nation-state resources decided to focus on it. The only surprise was the scope and the persistence. The attackers maintained access in some environments for over a year, moving laterally through systems that in many cases should never have been connected the way they were.
What makes this different from the usual parade of breaches is that telecommunications carriers are the nervous system of everything else. When they get compromised, you’re not just looking at customer data exposure. You’re looking at infrastructure that could theoretically support broad-spectrum surveillance or network disruption. That’s the threshold that finally forced the hand of federal regulators who had been content to let the market handle security.
The Technical Failures Were Predictable and Preventable
The CISA Salt Typhoon advisory didn’t hold back when it came to specifics. The primary attack vectors included legacy SNMP configurations still running with default credentials or minimal authentication, unpatched edge devices from vendors like Cisco and Fortinet, and a near-total absence of network segmentation that would have limited lateral movement. If you’ve been in infrastructure long enough, you recognize this pattern immediately. It’s the same set of failures we’ve documented in every major breach for the last fifteen years.
Take the Cisco IOS XE vulnerability, tracked as CVE-2023-20198, which carried a perfect 10.0 CVSS score. Patches were available for more than a year before Salt Typhoon operators started using it to establish initial access. That’s not a sophisticated zero-day scenario. That’s an organization that didn’t have functional patch management. And we’re talking about carriers responsible for routing a significant portion of US telecommunications traffic.
The unpatched edge devices and misconfigured network management protocols represent something worse than negligence. They represent a deliberate choice to prioritize uptime and operational convenience over segmentation and access controls. I understand that choice. Running a telecommunications network means managing systems that have been through multiple technology cycles, some devices running software that hasn’t been updated in a decade because replacement would require coordinated downtime. But understanding it doesn’t make it acceptable when the alternative is a foreign intelligence service’s direct access to your management infrastructure.
What bothers me most is that every element of this compromise was visible to anyone running basic network hygiene. You can scan for SNMP. You can track patch currency on edge devices. You can verify that your network management systems are properly segmented from production traffic. These aren’t exotic security measures. They’re table stakes.
The Regulatory Response and What It Actually Means
The FCC’s January 2025 cybersecurity rules are the first mandatory federal framework applied to telecommunications carriers under Section 105 of the Communications Act. Carriers are now required to submit annual cybersecurity risk management plans. If you’re in the industry, you already know this means a lot more than filing some paperwork with regulators.
Annual plans with regulatory oversight create liability where none existed before. If a carrier’s submitted plan claims certain network segmentation controls are in place, and an audit reveals they aren’t, that’s a documented failure. It also means third-party assessments will become standard practice across the industry. The FCC cybersecurity rulemaking proceeding established requirements that force carriers to maintain documented security postures at a level that regulators can verify.
This is where things get complicated for engineers actually building these systems. Regulatory compliance is not the same as security, but compliance requirements can force necessary security changes when nothing else will. The mandate for annual risk management plans essentially means every major telecom now has to formally acknowledge and document where their vulnerabilities live. That documentation becomes discoverable. It becomes something you have to defend.
What makes this different from other compliance frameworks is that the breaches themselves were so recent and so thorough that regulators understand exactly what to look for. They’re not writing rules based on general principles. They’re writing rules based on a specific failure case where billion-dollar organizations got thoroughly compromised through tactics and techniques that were well-documented at the time of the compromise.
The Remediation Reality and What it Costs
A February 2025 Mandiant report on post-Salt Typhoon remediation efforts found something that should concern anyone responsible for managing large network infrastructure. Seventy-three percent of affected organizations required full re-architecture of their carrier-grade network management interfaces. Not patches. Not configuration changes. Full re-architecture.
That’s a staggering scope of change. Re-architecting network management interfaces at telecommunications carrier scale isn’t just deploying new hardware and software. It means redesigning authentication flows, implementing proper segmentation that may not have existed before, potentially retiring systems that have been operational for years, and retraining teams on entirely different operational procedures.
The average remediation cost exceeded 47 million dollars per carrier. That’s not an outlier. That’s the mean across a large sample of affected organizations. Multiply that by nine carriers minimum and you’re approaching half a billion dollars in remediation spending across just the confirmed compromised carriers. The actual number is certainly higher when you include carriers that weren’t public about their involvement or haven’t disclosed the full scope of what was accessed.
From an engineering standpoint, this is actually the part that interests me most. When you’re forced to re-architect at that scale, you have an opportunity to get it right. You can implement defense in depth. You can build proper network segmentation from the ground up instead of bolting it onto systems designed for a different era. But you also have to do it without disrupting operations that millions of people depend on. That’s where the actual difficulty lives.
What This Means for How We Build Network Systems Going Forward
The mandate for annual cybersecurity risk management plans, combined with the massive remediation costs and the scale of the Salt Typhoon compromise, is fundamentally changing how network-adjacent systems need to be built. It’s not just about compliance anymore. There are now documented costs and liability exposure for the kinds of decisions that were previously treated as operational trade-offs.
If you’re an engineer designing network management infrastructure, you can’t make the case anymore that putting management systems on the same network as production traffic is acceptable because it’s operationally convenient. If you’re deploying edge devices, you can’t let them run unpatched because replacement would require downtime. If you’re managing authentication to critical infrastructure, you can’t rely on legacy protocols that nobody’s paying attention to.
The regulatory framework creates concrete incentives for doing things the difficult way instead of the easy way. That’s not always how regulation works. But when the regulation is written in response to a specific technical failure, and the failure was expensive and public, it tends to actually shift behavior.
The Salt Typhoon compromise happened because organizations at scale made deliberate decisions to prioritize operational convenience over security posture. They had years to make different decisions. The FCC decided to make different decisions mandatory. Whether that’s sufficient to actually prevent similar compromises remains to be seen, but it’s the most direct intervention in how telecom infrastructure gets built that we’ve seen in decades.
I’m curious how your organization is approaching these new requirements. If you’re building or maintaining network systems that will touch regulatory requirements, the time to think about your remediation strategy is now, not when an audit happens. What specific architectural changes are you planning, and what technical debt are you trying to avoid creating in the process?