CVE-2016-8858

high

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."

References

Advisories
More

https://security.netapp.com/advisory/ntap-20180201-0001/

https://security.gentoo.org/glsa/201612-18

https://security.FreeBSD.org/advisories/FreeBSD-SA-16:33.openssh.asc

https://github.com/openssh/openssh-portable/commit/ec165c392ca54317dbe3064a8c200de6531e89ad

http://www.securitytracker.com/id/1037057

http://www.securityfocus.com/bid/93776

http://www.openwall.com/lists/oss-security/2016/10/20/1

http://www.openwall.com/lists/oss-security/2016/10/19/3

https://ftp.openbsd.org/pub/OpenBSD/patches/6.0/common/013_ssh_kexinit.patch.sig

https://euvd.enisa.europa.eu/vulnerability/EUVD-2016-9683

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

https://bugzilla.redhat.com/show_bug.cgi?id=1384860

http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c?rev=1.127&content-type=text/x-cvsweb-markup

http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/kex.c.diff?r1=1.126&r2=1.127&f=h

Details

Source: Mitre, NVD

Published: 2016-12-09

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

EPSS

EPSS: 0.29462