ASA-2019-00597 – OpenSSH: Pre-Auth XMSS Integer Overflow


Allele Security Alert

ASA-2019-00597

Identifier(s)

ASA-2019-00597, CVE-2019-16905

Title

Pre-Auth XMSS Integer Overflow

Vendor(s)

The OpenBSD Project

Product(s)

OpenSSH

Affected version(s)

OpenSSH versions 7.7 through 7.9
OpenSSH versions 8.x before 8.1

Fixed version(s)

OpenSSH version 8.1

Proof of concept

Unknown

Description

OpenSSH 7.7 through 7.9 and 8.x before 8.1, when compiled with an experimental key type, has a pre-authentication integer overflow if a client or server is configured to use a crafted XMSS key. This leads to memory corruption and local code execution because of an error in the XMSS key parsing algorithm.

Technical details

Unknown

Credits

Adam Zabrocki

Reference(s)

SSD Advisory – OpenSSH Pre-Auth XMSS Integer Overflow – SSD Secure Disclosure
https://ssd-disclosure.com/archives/4033/ssd-advisory-openssh-pre-auth-xmss-integer-overflow

oss-security – Announce: OpenSSH 8.1 released
https://www.openwall.com/lists/oss-security/2019/10/09/1

CVE-2019-16905 – OpenSSH Pre-Auth XMSS Integer Overflow
http://blog.pi3.com.pl/?p=678

Announce: OpenSSH 8.1 released
https://seclists.org/oss-sec/2019/q4/9

CVS log for src/usr.bin/ssh/sshkey-xmss.c
https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/sshkey-xmss.c

src/usr.bin/ssh/sshkey-xmss.c – diff – 1.6
https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/sshkey-xmss.c.diff?r1=1.5&r2=1.6&f=h

OpenSSH: Release Notes
https://www.openssh.com/releasenotes.html

CVE-2019-16905 OpenSSH Pre-Auth Integer Overflow Vulnerability in NetApp Products
https://security.netapp.com/advisory/ntap-20191024-0003/

CVE-2019-16905
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-16905

CVE-2019-16905
https://nvd.nist.gov/vuln/detail/CVE-2019-16905

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Last modified: October 25, 2019

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