Spy campaigns expose how surveillance vendors hijack telecom networks to track phone locations

Security researchers have uncovered two separate spying campaigns that exploit known weaknesses in global telecom infrastructure to track people’s phone location tracking. According to a new report from Citizen Lab, these operations are likely just a small sample of widespread abuse by surveillance vendors seeking access to cellular networks.

The findings, published Thursday, reveal how vendors operate as “ghost” companies that pose as legitimate mobile providers. By piggybacking on network access, they can look up the real-time location data of targets without their knowledge. This practice, researchers warn, is far more common than previously understood.

How SS7 and Diameter flaws enable phone location tracking

One of the core issues lies in the insecurity of SS7, a set of protocols for 2G and 3G networks that has long been the backbone of global telecom routing. SS7 lacks authentication and encryption, making it easy for rogue operators to exploit. For years, experts have warned that governments and spyware makers can abuse these vulnerabilities to geolocate individuals.

Building on this, the newer Diameter protocol—designed for 4G and 5G—includes better security features. However, Citizen Lab highlights that many providers fail to implement these protections properly. Attackers can still fall back to exploiting SS7 when Diameter defenses are weak. This means that even modern networks remain vulnerable to phone location tracking.

Three telecom providers implicated in surveillance campaigns

Both campaigns share a common thread: they abused access to three specific telecom providers. These companies acted as entry and transit points, allowing surveillance vendors and their government clients to hide behind their infrastructure. The report names 019Mobile (Israel), Tango Networks U.K., and Airtel Jersey (now owned by Sure) as key players.

Sure CEO Alistair Beak told TechCrunch that the company does not lease signaling access for tracking purposes. He stated that Sure has implemented measures to block misuse, including monitoring and suspending suspicious activity. However, Tango Networks and 019Mobile did not respond to requests for comment. Gil Nagar, head of IT at 019Mobile, sent a letter to Citizen Lab saying the company “cannot confirm” that the identified infrastructure belongs to them.

Two distinct methods of phone location tracking

The first campaign relied on exploiting SS7 flaws, switching to Diameter when needed. Researchers believe this operation was run by an Israeli-based commercial geo-intelligence provider with deep telecom integration. The second campaign used a different approach: sending special SMS messages to a “high-profile” target’s SIM card.

These messages, known as SIMjacker attacks (first documented by Enea in 2019), communicate directly with the SIM card without alerting the user. They can turn a phone into a location tracking device. Gary Miller, one of the Citizen Lab researchers, noted that these attacks are geographically targeted and difficult to detect. “I’ve observed thousands of these attacks through the years,” he said, calling them “a fairly common exploit.”

Why this matters for privacy and security

Miller emphasized that these two campaigns are just the tip of the iceberg. “We only focused on two surveillance campaigns in a universe of millions of attacks across the globe,” he explained. The findings underscore how telecom network abuse remains a persistent threat, especially for high-profile individuals like journalists, activists, and political figures.

For more on how these vulnerabilities work, check out our guide on SS7 security risks and how to protect yourself. Also, learn about Diameter protocol exploits in 5G networks.

What can be done to stop phone location tracking?

Telecom providers must implement stronger authentication and monitoring for signaling protocols. Governments should enforce stricter regulations on surveillance vendors and their access to network infrastructure. For individuals, using encrypted communication apps and disabling location services when not needed can help reduce exposure.

As Citizen Lab’s report makes clear, the abuse of telecom networks for phone location tracking is not a theoretical risk—it’s happening now. The question is how quickly the industry will close these gaps before more targets are compromised.

Critical Nginx-ui MCP Flaw Actively Exploited in the Wild

A critical nginx-ui MCP flaw is being actively exploited, putting thousands of servers at risk. Tracked as CVE-2026-33032, this authentication bypass vulnerability carries a CVSS score of 9.8, making it one of the most severe threats currently facing system administrators. Discovered by Pluto Security, the flaw allows any network-adjacent attacker to take full control of an nginx server through a single unauthenticated API request.

Understanding the Nginx-ui MCP Flaw: Root Cause and Impact

So, what exactly went wrong? The vulnerability stems from a missing function call in the Model Context Protocol (MCP) implementation. Nginx-ui recently added MCP support, which splits communication across two HTTP endpoints. The /mcp endpoint properly includes both IP whitelisting and authentication middleware. However, the /mcp_message endpoint—which processes every tool invocation, including configuration writes and server restarts—shipped without any authentication check.

This omission exposes 12 MCP tools to unauthenticated callers. Seven of these are destructive, enabling attackers to inject nginx configurations, reload the server, and intercept all traffic passing through it. The remaining five provide reconnaissance capabilities, such as reading existing configs and mapping backend infrastructure. In other words, an attacker can silently take over your server and spy on your traffic.

Why This Nginx-ui MCP Flaw Demands Immediate Action

VulnCheck has already added the flaw to its Known Exploited Vulnerabilities (KEV) list. Meanwhile, Recorded Future’s Insikt Group independently flagged it in a recent report as one of 31 high-impact vulnerabilities exploited during March 2026, assigning it a risk score of 94 out of 100. These endorsements underscore the severity of the threat.

Pluto Security’s researchers used Shodan to identify over 2,600 publicly reachable nginx-ui instances across cloud providers including Alibaba Cloud, Oracle, and Tencent. Most were running on the default port 9000. The tool’s Docker image has been pulled more than 430,000 times, suggesting a much larger population of potentially vulnerable deployments sitting behind firewalls. Therefore, the actual number of at-risk instances could be significantly higher.

What Makes This Vulnerability Particularly Dangerous

This is the second MCP vulnerability Pluto Security has disclosed in recent weeks, following MCPwnfluence, an SSRF-to-RCE chain in the Atlassian MCP server. Both cases expose a recurring weakness: when MCP is connected to existing applications, its endpoints often inherit full capabilities without inheriting any of the security controls. As a result, a single missing check can compromise an entire system.

How to Protect Your Servers from the Nginx-ui MCP Flaw

The nginx-ui maintainers released a patch in version 2.3.4 just one day after disclosure. The fix amounted to 27 characters of added code, along with a regression test to prevent the same oversight from recurring. Organizations running nginx-ui with MCP enabled should take immediate action:

• Update to version 2.3.4 or later without delay.
• If patching is not possible, disable MCP functionality entirely.
• Restrict network access to the management interface using firewalls or VPNs.
• Review server logs and configuration directories for any unauthorized changes.

For more on securing your infrastructure, check out our guide on how to secure your nginx servers. Additionally, you may want to read about MCP security best practices to avoid similar pitfalls.

Conclusion: Act Now Before the Nginx-ui MCP Flaw Hits Your Network

Given the active exploitation and high CVSS score, this is not a vulnerability you can afford to ignore. The nginx-ui MCP flaw represents a clear and present danger to any organization using this popular web interface. By patching immediately, restricting access, and reviewing your logs, you can mitigate the risk. Remember, in the world of cybersecurity, a single missing line of code can open the door to disaster.

Vercel reveals customer data was stolen before its recent hack — and the breach may be bigger

App and website hosting powerhouse Vercel has disclosed that hackers managed to steal some of its customers’ data before the company discovered a major breach in early April. The revelation suggests the incident is more serious than first reported.

In an updated security notice, Vercel said its expanded investigation uncovered evidence of malicious activity on its network that predates the April intrusion. The company now believes a small number of customer accounts were compromised through social engineering, malware, or other tactics — separate from the main attack.

The Vercel customer data stolen in two waves

Vercel initially reported that its internal systems were breached after an employee downloaded an app from startup Context AI. Hackers exploited that app to hijack the employee’s work account and then infiltrate Vercel’s network.

However, the latest update indicates the Vercel data breach may have been ongoing longer than first thought. The company confirmed it found additional customer accounts compromised during the April incident, though it declined to specify how many or how far back the earlier breach dates.

“We have uncovered a small number of customer accounts with evidence of prior compromise that is independent of and predates this incident, potentially as a result of social engineering, malware, or other methods,” the company stated.

CEO links breach to infostealer malware

Vercel CEO Guillermo Rauch took to X to confirm that the hackers behind the attack have been active “beyond that startup’s compromise,” referring to Context AI, which itself confirmed a breach this week. Rauch pointed to early signs that the attackers relied on malware designed to steal valuable tokens — including keys to Vercel accounts and other services.

This behavior aligns with information-stealing malware, or infostealers, which often disguise themselves as legitimate software. Once installed, these programs collect and upload sensitive secrets from the victim’s computer, such as passwords and private keys, granting hackers access to any system those keys unlock.

“Once the attacker gets ahold of those keys, our logs show a repeated pattern: rapid and comprehensive API usage, with a focus on enumeration of non-sensitive environment variables,” Rauch explained.

The hackers used the hijacked Vercel employee’s account to reach internal systems, including customer credentials that were stored without encryption. This means the Vercel customer data stolen could include sensitive login information.

Context AI and the infostealer connection

Rauch’s comments add weight to earlier reports from security researchers that a Context AI employee’s computer was infected with infostealer malware after allegedly searching for Roblox game cheats. TechCrunch also reported that compliance startup Delve, accused of faking customer data, handled security certifications for Context AI.

Neither Vercel nor Context AI has confirmed the total number of affected customers. Both companies have warned that the breach may impact more organizations, and that additional victims could emerge in the coming weeks.

What this means for Vercel users

If you host applications or websites on Vercel, this incident underscores the importance of rotating API keys, enabling multi-factor authentication, and monitoring account activity for unusual behavior. Vercel has notified customers known to be affected so far, but the full scope remains unclear.

For a deeper look at how hosting providers handle security incidents, check out our guide on cloud hosting security best practices. You might also want to review how to rotate API keys safely to protect your own projects.

As investigations continue, the Vercel data breach serves as a stark reminder that even major platforms can fall victim to sophisticated malware campaigns. Stay vigilant, and consider infostealer malware protection tips to safeguard your credentials.