CVE-2019-16905

moderate-risk

Published 2019-10-09

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. NOTE: the XMSS implementation is considered experimental in all released OpenSSH versions, and there is no supported way to enable it when building portable OpenSSH.

Do I need to act?

0.27% chance of exploitation

EPSS score — low exploit probability

Not on CISA KEV list

No confirmed active exploitation reported to CISA

Patch status unknown

Check vendor advisories for fix availability and mitigation guidance

CVSS 7.8/10 High

LOCAL / LOW complexity

Affected Products (5)

Openssh

Cloud Backup

Steelstore Cloud Integrated Storage

Scalance X204Rna Firmware

Scalance X204Rna Ecc Firmware

Affected Vendors

Openbsd Siemens Netapp

References (18)

Issue Tracking https://bugzilla.suse.com/show_bug.cgi?id=1153537

Third Party Advisory https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf

Release Notes https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/sshkey-xmss.c

Patch https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/sshkey-xmss.c.diff?r1=...

Third Party Advisory https://security.gentoo.org/glsa/201911-01

Third Party Advisory https://security.netapp.com/advisory/ntap-20191024-0003/

Exploit https://ssd-disclosure.com/archives/4033/ssd-advisory-openssh-pre-auth-xmss-inte...

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

Mailing List https://www.openwall.com/lists/oss-security/2019/10/09/1