linux kernel vulnerability 4.9+

momurda

https://www.kb.cert.org/vuls/id/962459
Got this in an email blast from US CERT this morning.

scottalanmiller

Vulnerability Note VU#962459
Linux Kernel TCP implementation vulnerable to Denial of Service
Original Release date: 06 Aug 2018 | Last revised: 06 Aug 2018

The Linux kernel, versions 4.9+, is vulnerable to denial of service conditions with low rates of specially modified packets.

Description
CWE-400: Uncontrolled Resource Consumption ('Resource Exhaustion') - CVE-2018-5390

Linux kernel versions 4.9+ can be forced to make very expensive calls to tcp_collapse_ofo_queue() and tcp_prune_ofo_queue() for every incoming packet which can lead to a denial of service. An attacker can induce a denial of service condition by sending specially modified packets within ongoing TCP sessions. Maintaining the denial of service condition requires continuous two-way TCP sessions to a reachable open port. Thus, the attacks cannot be performed using spoofed IP addresses.

Impact
An remote attacker may be able to trigger a denial-of-service condition against a system with an available open port.

Solution
Apply a patch
Patches for the Linux kernel are available to address the vulnerability.

coliver

So not too bad a vulnerability. And it's already been patched. That's good.

Obsolesce

@coliver said in linux kernel vulnerability 4.9+:

So not too bad a vulnerability. And it's already been patched. That's good.

It is bad. What good is a server that's isn't providing a service? It may as well be turned off.

Patched already is great.

coliver

@obsolesce said in linux kernel vulnerability 4.9+:

@coliver said in linux kernel vulnerability 4.9+:

So not too bad a vulnerability. And it's already been patched. That's good.

It is bad. What good is a server that's isn't providing a service? It may as well be turned off.

Patched already is great.

It could be giving up secure and privileged information... at least with this one you know there is an issue.