CVE-2016-8858 Denial of service in n/a
Remote attackers can cause denial of service via memory consumption by sending duplicate KEXINIT requests to OpenSSH servers.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2016-8858?
CVE-2016-8858 is a high-severity denial of service vulnerability in OpenSSH, published on 9 Dec 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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."
Which versions are affected by CVE-2016-8858?
It affects 1 product.
Products include OpenSSH.
How do I fix CVE-2016-8858?
No fix published yet.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2016-8858 being exploited?
There is no known exploitation of CVE-2016-8858 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in OpenSSH
Sources
Also known as DEBIAN-CVE-2016-8858, GHSA-cfx4-r6f2-m2mc, UBUNTU-CVE-2016-8858.