CVE-2007-2243: Medium severity OpenBSD OpenSSH vulnerability

Published Apr 25, 2007
·
Updated

OpenSSH 4.6 and earlier, when ChallengeResponseAuthentication is enabled, allows remote attackers to determine the existence of user accounts by attempting to authenticate via S/KEY, which displays a different response if the user account exists, a similar issue to CVE-2001-1483.

Affected Software

62 affected components
OpenBSD OpenSSH=3.8
OpenBSD OpenSSH=3.8.1p1
OpenBSD OpenSSH=4.3p2
OpenBSD OpenSSH=3.2.2
OpenBSD OpenSSH=3.1
OpenBSD OpenSSH=3.0.2p1
OpenBSD OpenSSH=4.1
OpenBSD OpenSSH=3.8.1
OpenBSD OpenSSH=2.1.1
OpenBSD OpenSSH=3.7.1p2
OpenBSD OpenSSH=3.2.3p1
OpenBSD OpenSSH=3.1p1
OpenBSD OpenSSH=2.5.1
OpenBSD OpenSSH=2.9.9p2
OpenBSD OpenSSH=3.6.1p2
OpenBSD OpenSSH=3.9
OpenBSD OpenSSH=3.0
OpenBSD OpenSSH=1.2.1
OpenBSD OpenSSH=2.2
OpenBSD OpenSSH=3.2
OpenBSD OpenSSH=3.6
OpenBSD OpenSSH=1.2.3
OpenBSD OpenSSH=3.7
OpenBSD OpenSSH=4.0p1
OpenBSD OpenSSH=3.5p1
OpenBSD OpenSSH=3.0.1p1
OpenBSD OpenSSH=4.4
OpenBSD OpenSSH=3.7.1p1
OpenBSD OpenSSH=2.1
OpenBSD OpenSSH=1.2
OpenBSD OpenSSH=3.3
OpenBSD OpenSSH=3.2.2p1
OpenBSD OpenSSH=3.9.1p1
OpenBSD OpenSSH=3.0.2
OpenBSD OpenSSH=3.4p1
OpenBSD OpenSSH=3.6.1p1
OpenBSD OpenSSH=3.0.1
OpenBSD OpenSSH=2.9.9
OpenBSD OpenSSH=3.6.1
OpenBSD OpenSSH=4.1p1
OpenBSD OpenSSH=1.2.2
OpenBSD OpenSSH=4.2p1
OpenBSD OpenSSH=4.5
OpenBSD OpenSSH=2.9p1
OpenBSD OpenSSH=2.9
OpenBSD OpenSSH=3.7.1
OpenBSD OpenSSH=1.2.27
OpenBSD OpenSSH=4.2
OpenBSD OpenSSH=2.5.2
OpenBSD OpenSSH=2.3
OpenBSD OpenSSH=3.4
OpenBSD OpenSSH=4.4p1
OpenBSD OpenSSH=4.3p1
OpenBSD OpenSSH=3.5
OpenBSD OpenSSH=2.5
OpenBSD OpenSSH=3.0p1
OpenBSD OpenSSH=3.3p1
OpenBSD OpenSSH=4.3
OpenBSD OpenSSH=4.0
OpenBSD OpenSSH=3.9.1
OpenBSD OpenSSH=2.9p2
OpenBSD OpenSSH=4.6

Event History

Apr 25, 2007
CVE Published
04:19 PM
CVE Published
via MITRE·08:00 PM
Data Sourced
via MITRE·08:00 PM
Description

Frequently Asked Questions

1

What is the severity of CVE-2007-2243?

CVE-2007-2243 is considered a medium severity vulnerability due to the exposure of user account existence.

2

How do I fix CVE-2007-2243?

To mitigate CVE-2007-2243, disable ChallengeResponseAuthentication in the OpenSSH configuration.

3

Who is affected by CVE-2007-2243?

CVE-2007-2243 affects OpenSSH versions 4.6 and earlier.

4

What are the potential impacts of CVE-2007-2243?

Exploitation of CVE-2007-2243 can allow attackers to enumerate valid user accounts.

5

What configurations are related to CVE-2007-2243?

CVE-2007-2243 involves the configuration setting ChallengeResponseAuthentication in OpenSSH.

Contact

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