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+---
+title: 'Docker Image root User Hard-Coded Credential Vulnerability - CVE-2019-5021'
+date: 2019-05-09
+---
+
+# Docker Image root User Hard-Coded Credential Vulnerability - CVE-2019-5021
+
+[CVE-2019-5021](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-5021)
+
+## What is the problem?
+
+If you have `shadow` package installed in your Docker container and run your
+service as non-root an attacker who compromised your system via unrelated
+security vulnerabillity, or a user with shell access, could elevate the
+privileges to root within the container.
+
+## Who is affected?
+
+The issue only affects Docker images. If you used the Alpine linux installer,
+`setup-alpine`, you are not affected.
+
+You are not affected unless you have `shadow` or `linux-pam` packages
+installed.
+
+The issue was
+[fixed](https://git.alpinelinux.org/aports/commit/?id=7a2566ec8260ceacae81088ebe2ffe6526c3809e)
+in the following [Docker image releases]:
+- edge (20190228 snapshot)
+- v3.9.2
+- v3.8.4
+- v3.7.3
+- v3.6.5
+
+The following versions are EOL and still vulnerable:
+- v3.5
+- v3.4
+- v3.3
+
+## How can I fix it?
+
+Make sure that you use one of the supported releases and update your image.
+
+If you use any of older, unsupported releases, then you can fix it by adding
+this line to your Dockerfile:
+<code>
+# make sure root login is disabled
+RUN sed -i -e 's/^root::/root:!:/' /etc/shadow
+</code>
+
+Alternatively you could make sure that you don't have `linux-pam` installed.
+
+## What happened?
+
+