VPN blocks and the VLESS protocol vulnerability analysis
Sophia
2026-10-01
Read time
3 minutes
In September 2026, users in various regions of Russia experienced large-scale disruptions in VPN services. The restrictions affected many popular censorship-bypass tools, including those using the VLESS protocol. This intensification of control coincided with the end of the autumn elections, after which more than ten major services were blocked. Meanwhile, the regulator traditionally refrains from making official comments on the situation.
Strategy of combating bypass technologies
According to the official plans of regulatory agencies, the target is to increase the blocking efficiency of circumvention tools to 92% by 2030, and expand traffic monitoring systems to cover 98% of the Runet. Special attention is given to the VLESS protocol, which emerged in 2020. Efforts to block it based on signatures began in autumn 2025, when researcher Peter Losev confirmed the ability of automated systems to isolate this protocol. In early 2026, censors shifted to analyzing indirect traffic characteristics on the networks of major providers.
Technical systems for counteracting threats allow the start of the connection and the first few kilobytes of traffic to pass through for analysis. If the data flow appears randomized and does not match standard web surfing profiles, the session is forcibly terminated. This happens either by stopping packet routing or by sending spoofed connection reset packets to both sides. In spring 2026, similar tests targeted the VLESS TLS handshake process on standard ports.
Subnet blocking and application tracking
In summer 2026, the regulator shifted to blocking entire subnets of foreign hosting providers where VPN services were located, which also affected many private servers. Furthermore, research revealed that dozens of popular Russian mobile applications collect information about installed VPN clients on devices. Lawyer Sarkis Darbinyan linked the wave of restrictions specifically to the active collection of this data. In parallel, pressure increased on domestic hosters to prohibit them from providing capacity for creating proxy servers.
Results of practical tests
Practical tests of VLESS connections from various points in Russia demonstrated the uneven nature of the blockings. While connections remained relatively stable on broadband networks in major cities, regular failures were recorded on mobile internet. This confirms the targeted nature of the filtering and the use of "allowlists" on mobile networks, where access is granted exclusively to approved IP addresses, making any third-party VPN servers unreachable.
Detection methods and active probing
In addition to signature analysis and verifying the correspondence of domains in requests with real IP addresses, censors use the active scanning method. If the system detects a suspicious request, it sends a test request to the target IP address itself. If the server is not configured to disguise itself as a regular website and reveals its purpose, it is immediately blacklisted. Due to excessive load on equipment when processing these rules, large-scale failures periodically occur in the Runet, affecting banking applications.
Advice for developers and administrators
Specialists are advised to test server availability separately at the TCP connection level and the complete protocol handshake level. Tests should last at least a few minutes, as blocking is often triggered with a delay. If problems are detected from Russian operators, one should immediately contact the hoster to move the infrastructure to other subnets, after checking the server's functionality from abroad first.
For masquerading, one should not use the domains of the largest tech corporations, as the discrepancy of their addresses with real VPS is easily detected. It is better to choose less known resources or own domains. It is important for developers to provide users with dynamic links for automatic configuration updates and to set up automated availability monitoring on major telecommunication networks.
Using a reliable HiroVPN service will help bypass such technical restrictions and maintain stable network access without unnecessary difficulties.
