Spectre meltdown kernel update
Kernel Update required for "Spectre/Meltdown" issue ¶
NAME | Meltdown and Spectre Hardware Issues |
Description | Systems with microprocessors utilizing speculative execution and branch prediction may allow unauthorized disclosure of information to an attacker with local user access via a side-channel analysis. |
Related CVE(s) | CVE-2017-5715 CVE-2017-5753 CVE-2017-5754 |
NVD Severity | medium (attack range: local) |
Document Last Updated | January 07,2018 |
Summary ¶
- All unpatched versions of linux are vulnerable when running on affected hardware, across all platforms (AWS, GCE, etc)
- Patches are included in Linux 4.4.110 for 4.4, 4.9.75 for 4.9, 4.14.12 for 4.14.
- kOps can run an image of your choice, so we can only provide detailed advice for the default image.
- By default, kOps runs an image that includes the 4.4 kernel. An updated image is available with the patched version (4.4.110). Users running the default image are strongly encouraged to upgrade.
- If running another image please see your distro for updated images.
CVEs ¶
Three CVEs have been made public, representing different ways to exploit the same underlying speculative-execution hardware issue:
- Variant 1: bounds check bypass (CVE-2017-5753)
- Variant 2: branch target injection (CVE-2017-5715)
- Variant 3: rogue data cache load (CVE-2017-5754)
The kernel updates that are the subject of this advisory are primarily intended to mitigate CVE-2017-5753 and CVE-2017-5754.
Detecting vulnerable software ¶
If you do not see "Kernel/User page tables isolation: enabled" in dmesg
, you are vulnerable.
dmesg -H | grep 'page tables isolation'
[ +0.000000] Kernel/User page tables isolation: enabled
Impacted Maintained Component(s) ¶
- Patches were released for the linux kernel 2018-01-05. All images prior to this date likely need updates.
- The kubernetes/kops maintained AMI is the maintained component that is vulnerable, although this likely affects all users.
Fixed Versions ¶
For the kops-maintained AMIs, the following AMIs contain an updated kernel:
- kope.io/k8s-1.5-debian-jessie-amd64-hvm-ebs-2018-01-05
- kope.io/k8s-1.6-debian-jessie-amd64-hvm-ebs-2018-01-05
- kope.io/k8s-1.7-debian-jessie-amd64-hvm-ebs-2018-01-05
- kope.io/k8s-1.8-debian-jessie-amd64-hvm-ebs-2018-01-05
- kope.io/k8s-1.8-debian-stretch-amd64-hvm-ebs-2018-01-05
These are the images that are maintained by the kubernetes/kops project; please refer to other vendors for the appropriate AMI version.
Update Process ¶
For all examples please replace $CLUSTER
with the appropriate kOps cluster
name.
List instance groups ¶
kops get ig --name $CLUSTER
Update the image for each instance group ¶
Update the instance group with the appropriate image version via a kops
edit
command or kops replace -f mycluster.yaml
.
Preview changes ¶
Perform a dry-run update, verifying that all instance groups are updated.
kops update cluster --name $CLUSTER
Apply changes ¶
Update the cluster configuration, so that new instances will start with the updated image.
kops update cluster --name $CLUSTER --yes
Preview rolling update ¶
Perform a dry-run rolling-update, to verify that all instance groups will be rolled.
kops rolling-update cluster --name $CLUSTER
Roll the cluster ¶
Performing a rolling-update of the cluster ensures that all old instances and replaced with new instances, running the updated image.
kops rolling-update cluster --name $CLUSTER --yes
Resources / Notes ¶
- https://aws.amazon.com/de/security/security-bulletins/AWS-2018-013/
- https://security.googleblog.com/2018/01/todays-cpu-vulnerability-what-you-need.html
- https://coreos.com/blog/container-linux-meltdown-patch
- https://spectreattack.com/
- https://xenbits.xen.org/xsa/advisory-254.html
- https://googleprojectzero.blogspot.co.uk/2018/01/reading-privileged-memory-with-side.html
- Paper: https://spectreattack.com/spectre.pdf
- https://01.org/security/advisories/intel-oss-10002
- https://meltdownattack.com/
- http://blog.cyberus-technology.de/posts/2018-01-03-meltdown.html
- Paper: https://meltdownattack.com/meltdown.pdf
- https://01.org/security/advisories/intel-oss-10003