SB2019100932 - Privilege escalation in OpenSSH
Published: October 9, 2019 Updated: October 24, 2019
Security Bulletin ID
SB2019100932
Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Integer overflow (CVE-ID: CVE-2019-16905)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to integer overflow within the XMSS key parsing algorithm. A local user can configure the server or client to use a specially crafted XMSS private key, trigger integer overflow and execute arbitrary code on the target system with elevated privileges.
Remediation
Install update from vendor's website.
References
- https://0day.life/exploits/0day-1009.html
- https://bugzilla.suse.com/show_bug.cgi?id=1153537
- https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/sshkey-xmss.c
- https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/sshkey-xmss.c.diff?r1=1.5&r2=1.6&f=h
- https://security.netapp.com/advisory/ntap-20191024-0003/
- https://ssd-disclosure.com/archives/4033/ssd-advisory-openssh-pre-auth-xmss-integer-overflow
- https://www.openssh.com/releasenotes.html
- https://www.openwall.com/lists/oss-security/2019/10/09/1