CVE-2016-6515: Input Validation

Published Aug 7, 2016
·
Updated

A denial of service vulnerability was found in openssh. The authpassword function in auth-passwd.c in sshd in OpenSSH before 7.3 does not limit password lengths for password authentication, which allows remote attackers to cause a denial of service (crypt CPU consumption) via a long string.

References:

http://seclists.org/oss-sec/2016/q3/215

Upstream fix:

https://github.com/openssh/openssh-portable/commit/fcd135c9df440bcd2d5870405ad3311743d78d97

Affected Software

3 affected componentsFixes available
redhat/openssh<7.3
7.3
OpenBSD OpenSSH<=7.2
Fedoraproject Fedora=24

Event History

Aug 7, 2016
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
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Frequently Asked Questions

1

What is the severity of CVE-2016-6515?

CVE-2016-6515 has been classified as a denial of service vulnerability that can lead to high CPU consumption due to unrestricted password length in OpenSSH.

2

How do I fix CVE-2016-6515?

To fix CVE-2016-6515, upgrade OpenSSH to version 7.3 or higher.

3

What versions of OpenSSH are affected by CVE-2016-6515?

CVE-2016-6515 affects OpenSSH versions prior to 7.3.

4

What is the impact of CVE-2016-6515 on systems?

The impact of CVE-2016-6515 is that it allows remote attackers to exhaust the CPU resources of a vulnerable system.

5

Is CVE-2016-6515 exploitable remotely?

Yes, CVE-2016-6515 is exploitable remotely through password authentication.

Contact

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