Dropbear SSH client hostkey mismatch weak security

dropbear-hostkey-weak-security (32762)

Low Risk

Description:

Dropbear SSH client could provide weaker than expected security. Hostkey mismatches do not create warning messages for the user. An authenticated remote attacker could exploit this vulnerability to possibly conduct man-in-the-middle attacks.

*CVSS:

Base Score:	3.2
Access Vector:	Remote
Access Complexity:	Low
Authentication:	Required
Confidentiality Impact:	Partial
Integrity Impact:	Partial
Availability Impact:	None
Temporal Score:	2.4
Exploitability:	Unproven
Remediation Level:	Official-Fix
Report Confidence:	Confirmed

Consequences:

Bypass Security

Remedy:

Upgrade to the latest version of Dropbear SSH client (0.49 or later), available from the Dropbear Web page. See References.

References:

• Dropbear Web page: CHANGES.
• BID-22761: Dropbear Hostkey Mismatch Warning Weakness
• CVE-2007-1099: dbclient in Dropbear SSH client before 0.49 does not sufficiently warn the user when it detects a hostkey mismatch, which might allow remote attackers to conduct man-in-the-middle attacks.
• OSVDB ID: 32088: Dropbear SSH dbclient Hostkey Mismatch Weakness
• SA24345: Dropbear hostkey Mismatch Warning Weakness
• VUPEN/ADV-2007-0785: Dropbear SSH Hostkey Mismatch Confirmation and Warning Bypass Weakness

Platforms Affected:

• Matt Johnston Dropbear SSH Client prior to 0.49

Reported:

Mar 01, 2007

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For corrections or additions please email xforce@iss.net

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The information within this database may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. In no event shall IBM be held liable for any damages whatsoever arising out of or in connection with the use or spread of this information.

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