The tl;dr of this post is that I want to scan my Alpine based images locally for vulnerabilities before pushing the image to an online registry. Why? Well I think it makes sense that developers have the option of checking for CVE's locally and at build time. They may choose to ignore the results but it's nice to have the option. In future this could perhaps be made into a plugin or included with the docker build function.
I mentioned this to a few folks at DockerCon and decided to put together a simple demo. Using the MultiStage build feature in Docker 17.05 we can append a CVE scan stage into our build and run a scan at build time. I also have a service running in Docker Swarm that updates the CVE database each hour and is available to all cluster nodes where image builds happen. That's for another day.
Let's get started. This first step will take a few minutes since it downloads the CVE database which is around 800mb.
Build the cvechecker image. This image will contain the cvechecker tool and the CVE database. More details on cvechecker can be found here
docker build -t cvechecker:latest .
There are lots of ways to run the CVE scan. Firstly let's try using the MultiStage Dockerfile to build a Wordpress container and then run the scan.
docker build -t wordpress:latest --no-cache -f Dockerfile.wordpress .
Copy the CVE.log from the image and check inside
docker run -t --rm -v ${PWD}:/results wordpress:latest /bin/sh -c "mv /tmp/CVE.log /results/wordpress.CVE.log"
File "/usr/lib/libbz2.so.1.0.6" (CPE = cpe:/a:bzip:bzip2:1.0.6:::) on host 837a64dcc771 (key 837a64dcc771)
Potential vulnerability found (CVE-2016-3189)
CVSS Score is 4.3
Full vulnerability match (incl. edition/language)
This CVE was detected in the libarchive package. This package is not needed and was just an example. Remove libarchive from the Dockerfile and rebuild. No vulnerability found. Great job.
Using the MultiStage Dockerfile we can supply a list of images and scan them all sequentially for CVE's. We could use docker-compose to replace the image name as an environment variable but in this case we will just use a bit of bash.
./bulk_cve_scan.sh list_of_images.txt
This will pull each image, copy the contents into the cvechecker image, generate a list of executables and run the cvechecker. A results file is created per image and a final report is created.
*************************************
---> Image : nginx:1.13.0-alpine-perl
---> Sha : sha256:dcf49000bf50c4e93d6cc84c96f8acf985998154e09f6301cff7c62314811604
---> Created : 2017-04-25T17:25:05.511678526Z
---> Log : ./results/nginx:1.13.0-alpine-perl.CVE.log
---> Status : 1 CVE's found
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3189
*************************************
*************************************
---> Image : redis:3.2.8-alpine
---> Sha : sha256:83638a6d3af20698d5e207febe714ac46a23a98e1d86ba36fe502fadc788daa3
---> Created : 2017-03-03T23:33:08.415849842Z
---> Log : ./results/redis:3.2.8-alpine.CVE.log
---> Status : No CVE's found
*************************************
*************************************
---> Image : logstash:1.5.6-alpine
---> Sha : sha256:6a7afab35097ffcacf6445366065b234371902240e2d9bf41bb3d64386352db6
---> Created : 2017-03-07T18:57:08.447747089Z
---> Log : ./results/logstash:1.5.6-alpine.CVE.log
---> Status : 1 CVE's found
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3189
*************************************
*************************************
---> Image : logstash:1-alpine
---> Sha : sha256:6a7afab35097ffcacf6445366065b234371902240e2d9bf41bb3d64386352db6
---> Created : 2017-03-07T18:57:08.447747089Z
---> Log : ./results/logstash:1-alpine.CVE.log
---> Status : 1 CVE's found
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3189
*************************************
*************************************
---> Image : elasticsearch:1.7.6-alpine
---> Sha : sha256:59103e15fe949d9735eb4ff885abb6fb5ff50bc587acb4075ac10c0d9bbb0467
---> Created : 2017-04-04T23:28:36.351775037Z
---> Log : ./results/elasticsearch:1.7.6-alpine.CVE.log
---> Status : 1 CVE's found
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3189
*************************************
*************************************
---> Image : wordpress:4.7.4-php7.1-fpm-alpine
---> Sha : sha256:80052e2343db98ce7ccf00b582fe024b40e07a497fdcc43f5814ba93b960d2d2
---> Created : 2017-05-06T00:15:39.364168997Z
---> Log : ./results/wordpress:4.7.4-php7.1-fpm-alpine.CVE.log
---> Status : 46 CVE's found
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-0903
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-1516
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-1517
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-1518
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-2753
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-3469
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-3486
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-4031
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-4226
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-1420
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-2583
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-2691
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-2692
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-6303
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-6304
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-2079
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-3963
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-4098
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-7247
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-2446
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-4019
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-4028
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-5026
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-1848
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-1849
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-1850
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-3677
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-3682
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-3833
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-3834
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-3836
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-3837
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-3838
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0075
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0087
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0101
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0102
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0114
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0484
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0490
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-1696
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-1697
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-3160
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-3166
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-3177
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-6321
*************************************
*************************************
---> Image : ruby:2.1.8-alpine
---> Sha : sha256:f6611d75e6dc337005a23816143cfa40f96fab41860f563665c36efbb541b1e6
---> Created : 2016-03-30T21:01:49.675295954Z
---> Log : ./results/ruby:2.1.8-alpine.CVE.log
---> Status : 14 CVE's found
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2105
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2106
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2107
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2109
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2176
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2177
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2178
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2179
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2180
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2181
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2182
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3189
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-6302
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-6303
*************************************
*************************************
---> Image : consul:v0.7.0
---> Sha : sha256:2ba9010ee3cc0251be45e8b55f3154eb421df841cd93a375f9f5ab334d848291
---> Created : 2016-10-18T22:59:58.369872799Z
---> Log : ./results/consul:v0.7.0.CVE.log
---> Status : No CVE's found
*************************************
*************************************
---> Image : python:3.4.5-alpine
---> Sha : sha256:0eb0091592b3d8aab929e19041330d307e0e3302cf58ae8753276a2860c45037
---> Created : 2016-12-27T21:39:19.757995673Z
---> Log : ./results/python:3.4.5-alpine.CVE.log
---> Status : 1 CVE's found
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3189
*************************************
*************************************
---> Image : rabbitmq:3.6.6-alpine
---> Sha : sha256:1f17c5fffd2d35099050f4d224be92c424b90550cc65c76570be71d368e637cc
---> Created : 2017-03-03T23:32:16.463770425Z
---> Log : ./results/rabbitmq:3.6.6-alpine.CVE.log
---> Status : No CVE's found
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I like free stuff. This isn't bullet-proof but it's already found a few questionable images which I would previously have used without question.
I'll tidy this up in the coming weeks and perhaps use Goss as a trigger for the CVE check.
Feel free to contact me for more details, banter, pull requests etc
@tomwillfixit @Shipitcon @DockerDublin #DockerCaptain