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Home >> Browse Vulnerability Assessment Database >> Denial of Service >> Dropbear Authorization-Pending Denial of Service Vulnerability

Vulnerability Assessment Details

Dropbear Authorization-Pending Denial of Service Vulnerability

Vulnerability Assessment Summary
Checks for authorization pending connection limit in Dropbear SSH server

Detailed Explanation for this Vulnerability Assessment

Summary :

The remote SSH server is susceptible to denial of service attacks.

Description :

The remote host is running Dropbear, a small, open-source SSH server.

The version of Dropbear installed on the remote host by default has a limit of
30 connections in the authorization-pending state
subsequent connections are
closed immediately. This issue can be exploited trivially by an
unauthenticated attacker to deny service to legitimate users.

See also :

http://www.securityfocus.com/archive/1/426999/30/0/threaded
http://lists.grok.org.uk/pipermail/full-disclosure/2006-March/042849.html

Solution :

Upgrade to Dropbear 0.48 or later.

Network Security Threat Level:

Low / CVSS Base Score : 2
(AV:R/AC:L/Au:NR/C:N/A:P/I:N/B:N)

Networks Security ID: 17024

Vulnerability Assessment Copyright: This script is Copyright (C) 2006 Tenable Network Security

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