AS266140: the CMC TELECOM LTDA network

AS266140 is an internet Autonomous System operated by CMC TELECOM LTDA (Brazil). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS266140?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS266140 was assigned to CMC TELECOM LTDA by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS266140 currently announces 1 IPv4 block(s), totaling about 1 thousand addresses (1,024 in all), registered in Brazil. Services from CMC TELECOM LTDA are reached through these addresses.

What it means to see AS266140 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS266140. That means the other end sits on the CMC TELECOM LTDA network (Brazil). It can be legitimate — a cloud service, an ISP, a CDN — or an unexpected connection worth checking.

How to see every connection and network your devices reach

Tracing one connection's ASN at a time is tedious. Sentinela, by PC Monitor, maps the devices on your network, shows what is exposed to the internet and helps flag suspicious connections and devices — running on your Windows. Meet Sentinela.