ThreatCluster

Telnet Vulnerability Exposes 800,000 Servers to Active Attacks

First seen 28 Jan 2026, 02:54 UTC • •25

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ThreatCluster •March 12, 2026 at 13:27 UTC

A critical vulnerability in the telnetd server software has been identified, putting approximately 800,000 servers at risk. The U.S. Cybersecurity and Infrastructure Security Agency has added this flaw to its catalog of known exploited vulnerabilities, prompting urgent attention from system administrators.

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3 entities, 2 inferred relationships (STIX 2.1).

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Affected Platform (1)

Telnetd

Tool (1)

Telnet

Vulnerability (1)

Telnet Flaw

Relationships

Telnet exploits Telnet Flaw
Telnet Flaw targets Telnetd

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