Description
The kex_input_kexinit function in kex.c in OpenSSH 6.x and 7.x through 7.3 allows remote attackers to cause a denial of service (memory consumption) by sending many duplicate KEXINIT requests. NOTE: a third party reports that "OpenSSH upstream does not consider this as a security issue."
Exploits (1)
References (13)
Core 13
Core References
Third Party Advisory, VDB Entry vdb-entry
http://www.securityfocus.com/bid/93776
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2016/10/20/1
Mailing List, Third Party Advisory mailing-list
http://www.openwall.com/lists/oss-security/2016/10/19/3
Third Party Advisory vendor-advisory
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:33.openssh.asc
Third Party Advisory, VDB Entry vdb-entry
http://www.securitytracker.com/id/1037057
Third Party Advisory vendor-advisory
https://security.gentoo.org/glsa/201612-18
Issue Tracking, Vendor Advisory
http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c.diff?r1=1.126&r2=1.127&f=h
Issue Tracking, Vendor Advisory
http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c?rev=1.127&content-type=text/x-cvsweb-markup
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1384860
Patch, Vendor Advisory
https://ftp.openbsd.org/pub/OpenBSD/patches/6.0/common/013_ssh_kexinit.patch.sig
Issue Tracking, Patch, Third Party Advisory
https://github.com/openssh/openssh-portable/commit/ec165c392ca54317dbe3064a8c200de6531e89ad
Third Party Advisory
https://security.netapp.com/advisory/ntap-20180201-0001/
Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
Scores
CVSS v3
7.5
EPSS
0.2687
EPSS Percentile
96.4%
Attack Vector
NETWORK
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Details
CWE
CWE-399
Status
published
Products (6)
openbsd/openssh
6.8
openbsd/openssh
6.9
openbsd/openssh
7.0
openbsd/openssh
7.1
openbsd/openssh
7.2
openbsd/openssh
7.3
Published
Dec 09, 2016
Tracked Since
Feb 18, 2026