CVE-2021-27342

An authentication brute-force protection mechanism bypass in telnetd in D-Link Router model DIR-842 firmware version 3.0.2 allows a remote attacker to circumvent the anti-brute-force cool-down delay period via a timing-based side-channel attack

• CWE-203

• https://blog.whtaguy.com/2021/05/d-link-router-cve-2021-27342.htmlExploit, Third Party Advisory
• https://github.com/guywhataguy/D-Link-CVE-2021-27342-exploit/blob/main/dlink-telnet-exploit-CVE-2021-27342.pyExploit, Third Party Advisory
• https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10225Vendor Advisory
• https://blog.whtaguy.com/2021/05/d-link-router-cve-2021-27342.htmlExploit, Third Party Advisory
• https://github.com/guywhataguy/D-Link-CVE-2021-27342-exploit/blob/main/dlink-telnet-exploit-CVE-2021-27342.pyExploit, Third Party Advisory
• https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10225Vendor Advisory

Published

May 17, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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