D-Link DIR-2640 HNAP LoginPassword Authentication Bypass Vulnerability. This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of D-Link DIR-2640 routers. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the web management interface, which listens on TCP port 80 by default. A specially crafted login request can cause authentication to succeed without providing proper credentials. An attacker can leverage this vulnerability to bypass authentication on the system. Was ZDI-CAN-19549.

Zero Day Initiative AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Zero Day Initiative CWE-303

Zero Day Initiative https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10323 [No types assigned]

Zero Day Initiative https://www.zerodayinitiative.com/advisories/ZDI-23-544/ [No types assigned]