On January 14, 2026, global telnet traffic dropped 59% abruptly due to potential port 23 filtering by U.S. internet providers, coinciding with the discovery of CVE-2026-24061, a critical telnet vulnerability. Eighteen ASNs lost all telnet sessions, and five countries dropped from data completely. The post suggests the drop was a response to an exploitable vulnerability, emphasizing the importance of patching or disabling GNU Inetutils telnetd. The sustained reduction in telnet traffic indicates a shift away from insecure protocols among ISPs.
https://www.labs.greynoise.io/grimoire/2026-02-10-telnet-falls-silent/