CVE-2021-21284

In Docker before versions 9.03.15, 20.10.3 there is a vulnerability involving the --userns-remap option in which access to remapped root allows privilege escalation to real root. When using "--userns-remap", if the root user in the remapped namespace has access to the host filesystem they can modify files under "/var/lib/docker/<remapping>" that cause writing files with extended privileges. Versions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.

In Docker before versions 9.03.15, 20.10.3 there is a vulnerability involving the --userns-remap option in which access to remapped root allows privilege escalation to real root. When using "--userns-remap", if the root user in the remapped namespace has access to the host filesystem they can modify files under "/var/lib/docker/<remapping>" that cause writing files with extended privileges. Versions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.

Impact

When using --userns-remap, if the root user in the remapped namespace has access to the host filesystem they can modify files under /var/lib/docker/<remapping> that cause writing files with extended privileges.

Patches

Versions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.

Credits

Maintainers would like to thank Alex Chapman for discovering the vulnerability; @awprice, @nathanburrell, @raulgomis, @chris-walz, @erin-jensby, @bassmatt, @mark-adams, @dbaxa for working on it and Zac Ellis for responsibly disclosing it to [email protected]

Docker is an open source project to build, ship and run any application as a lightweight container. Docker containers are both hardware-agnostic and platform-agnostic. This means they can run anywhere, from your laptop to the largest EC2 compute instance and everything in between - and they don't require you to use a particular language, framework or packaging system. That makes them great building blocks for deploying and scaling web apps, databases, and backend services without depending on a particular stack or provider.

Security Fix(es):

In Docker before versions 9.03.15, 20.10.3 there is a vulnerability involving the --userns-remap option in which access to remapped root allows privilege escalation to real root. When using --userns-remap, if the root user in the remapped namespace has access to the host filesystem they can modify files under /var/lib/docker/<remapping> that cause writing files with extended privileges. Versions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.(CVE-2021-21284)

In Docker before versions 9.03.15, 20.10.3 there is a vulnerability in which pulling an intentionally malformed Docker image manifest crashes the dockerd daemon. Versions 20.10.3 and 19.03.15 contain patches that prevent the daemon from crashing.(CVE-2021-21285)

In Docker before versions 9.03.15, 20.10.3 there is a vulnerability involving the --userns-remap option in which access to remapped root allows privilege escalation to real root. When using "--userns-remap", if the root user in the remapped namespace has access to the host filesystem they can modify files under "/var/lib/docker/<remapping>" that cause writing files with extended privileges. Versions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.

This update for containerd, docker, docker-runc, golang-github-docker-libnetwork fixes the following issues:

Security issues fixed:

• CVE-2020-15257: Fixed a privilege escalation in containerd (bsc#1178969).
• CVE-2021-21284: potential privilege escalation when the root user in the remapped namespace has access to the host filesystem (bsc#1181732)
• CVE-2021-21285: pulling a malformed Docker image manifest crashes the dockerd daemon (bsc#1181730)

Non-security issues fixed:

• Update Docker to 19.03.15-ce. See upstream changelog in the packaged /usr/share/doc/packages/docker/CHANGELOG.md. This update includes fixes for bsc#1181732 (CVE-2021-21284) and bsc#1181730 (CVE-2021-21285).

• Only apply the boo#1178801 libnetwork patch to handle firewalld on openSUSE. It appears that SLES doesn't like the patch. (bsc#1180401)

• Update to containerd v1.3.9, which is needed for Docker v19.03.14-ce and fixes CVE-2020-15257. bsc#1180243

• Update to containerd v1.3.7, which is required for Docker 19.03.13-ce. bsc#1176708

• Update to Docker 19.03.14-ce. See upstream changelog in the packaged /usr/share/doc/packages/docker/CHANGELOG.md. CVE-2020-15257 bsc#1180243 https://github.com/docker/docker-ce/releases/tag/v19.03.14

• Enable fish-completion

• Add a patch which makes Docker compatible with firewalld with nftables backend. Backport of https://github.com/moby/libnetwork/pull/2548 (bsc#1178801, SLE-16460)

• Update to Docker 19.03.13-ce. See upstream changelog in the packaged /usr/share/doc/packages/docker/CHANGELOG.md. bsc#1176708

• Fixes for %_libexecdir changing to /usr/libexec (bsc#1174075)

• Emergency fix: %requires_eq does not work with provide symbols, only effective package names. Convert back to regular Requires.

• Update to Docker 19.03.12-ce. See upstream changelog in the packaged /usr/share/doc/packages/docker/CHANGELOG.md.

• Use Go 1.13 instead of Go 1.14 because Go 1.14 can cause all sorts of spurrious errors due to Go returning -EINTR from I/O syscalls much more often (due to Go 1.14's pre-emptive goroutine support).

• Add BuildRequires for all -git dependencies so that we catch missing dependencies much more quickly.

• Update to libnetwork 55e924b8a842, which is required for Docker 19.03.14-ce. bsc#1180243

• Add patch which makes libnetwork compatible with firewalld with nftables backend. Backport of https://github.com/moby/libnetwork/pull/2548 (bsc#1178801, SLE-16460)

This update was imported from the SUSE:SLE-15:Update update project.

This update for containerd, docker, runc fixes the following issues:

Docker was updated to 20.10.6-ce (bsc#1184768, bsc#1182947, bsc#1181594)

• Switch version to use -ce suffix rather than _ce to avoid confusing other tools (bsc#1182476).
• CVE-2021-21284: Fixed a potential privilege escalation when the root user in the remapped namespace has access to the host filesystem (bsc#1181732)
• CVE-2021-21285: Fixed an issue where pulling a malformed Docker image manifest crashes the dockerd daemon (bsc#1181730).
• btrfs quotas being removed by Docker regularly (bsc#1183855, bsc#1175081)

runc was updated to v1.0.0~rc93 (bsc#1182451, bsc#1175821 bsc#1184962).

• Use the upstream runc package (bsc#1181641, bsc#1181677, bsc#1175821).
• Fixed /dev/null is not available (bsc#1168481).
• CVE-2021-30465: Fixed a symlink-exchange attack vulnarability (bsc#1185405).

containerd was updated to v1.4.4

• CVE-2021-21334: Fixed a potential information leak through environment variables (bsc#1183397).
• Handle a requirement from docker (bsc#1181594).

This update was imported from the SUSE:SLE-15:Update update project.

This update for containerd, docker, runc fixes the following issues:

Docker was updated to 20.10.6-ce (bsc#1184768, bsc#1182947, bsc#1181594)

• Switch version to use -ce suffix rather than _ce to avoid confusing other tools (bsc#1182476).
• CVE-2021-21284: Fixed a potential privilege escalation when the root user in the remapped namespace has access to the host filesystem (bsc#1181732)
• CVE-2021-21285: Fixed an issue where pulling a malformed Docker image manifest crashes the dockerd daemon (bsc#1181730).
• btrfs quotas being removed by Docker regularly (bsc#1183855, bsc#1175081)

runc was updated to v1.0.0~rc93 (bsc#1182451, bsc#1175821 bsc#1184962).

• Use the upstream runc package (bsc#1181641, bsc#1181677, bsc#1175821).
• Fixed /dev/null is not available (bsc#1168481).
• CVE-2021-30465: Fixed a symlink-exchange attack vulnarability (bsc#1185405).

containerd was updated to v1.4.4

• CVE-2021-21334: Fixed a potential information leak through environment variables (bsc#1183397).
• Handle a requirement from docker (bsc#1181594).

These are all security issues fixed in the docker-20.10.6_ce-2.1 package on the GA media of openSUSE Tumbleweed.

These are all security issues fixed in the docker-stable-24.0.9_ce-15.1 package on the GA media of openSUSE Tumbleweed.

This update for containerd, docker, docker-runc, golang-github-docker-libnetwork fixes the following issues:

Security issues fixed:

• CVE-2020-15257: Fixed a privilege escalation in containerd (bsc#1178969).
• CVE-2021-21284: potential privilege escalation when the root user in the remapped namespace has access to the host filesystem (bsc#1181732)
• CVE-2021-21285: pulling a malformed Docker image manifest crashes the dockerd daemon (bsc#1181730)

Non-security issues fixed:

• Update Docker to 19.03.15-ce. See upstream changelog in the packaged /usr/share/doc/packages/docker/CHANGELOG.md. This update includes fixes for bsc#1181732 (CVE-2021-21284) and bsc#1181730 (CVE-2021-21285).

• Only apply the boo#1178801 libnetwork patch to handle firewalld on openSUSE. It appears that SLES doesn't like the patch. (bsc#1180401)

• Update to containerd v1.3.9, which is needed for Docker v19.03.14-ce and fixes CVE-2020-15257. bsc#1180243

• Update to containerd v1.3.7, which is required for Docker 19.03.13-ce. bsc#1176708

• Update to Docker 19.03.14-ce. See upstream changelog in the packaged /usr/share/doc/packages/docker/CHANGELOG.md. CVE-2020-15257 bsc#1180243 https://github.com/docker/docker-ce/releases/tag/v19.03.14

• Enable fish-completion

• Add a patch which makes Docker compatible with firewalld with nftables backend. Backport of https://github.com/moby/libnetwork/pull/2548 (bsc#1178801, SLE-16460)

• Update to Docker 19.03.13-ce. See upstream changelog in the packaged /usr/share/doc/packages/docker/CHANGELOG.md. bsc#1176708

• Fixes for %_libexecdir changing to /usr/libexec (bsc#1174075)

• Emergency fix: %requires_eq does not work with provide symbols, only effective package names. Convert back to regular Requires.

• Update to Docker 19.03.12-ce. See upstream changelog in the packaged /usr/share/doc/packages/docker/CHANGELOG.md.

• Use Go 1.13 instead of Go 1.14 because Go 1.14 can cause all sorts of spurrious errors due to Go returning -EINTR from I/O syscalls much more often (due to Go 1.14's pre-emptive goroutine support).

• Add BuildRequires for all -git dependencies so that we catch missing dependencies much more quickly.

• Update to libnetwork 55e924b8a842, which is required for Docker 19.03.14-ce. bsc#1180243

• Add patch which makes libnetwork compatible with firewalld with nftables backend. Backport of https://github.com/moby/libnetwork/pull/2548 (bsc#1178801, SLE-16460)

This update for containerd, docker, docker-runc, golang-github-docker-libnetwork fixes the following issues:

Update Docker to 19.03.15-ce:

• CVE-2021-21284: potential privilege escalation when the root user in the remapped namespace has access to the host filesystem (bsc#1181732)
• CVE-2021-21285: malformed Docker image manifest crashes the dockerd daemon (bsc#1181730)
• CVE-2020-15157: containerd: credentials leaking during image pull (bsc#1177598)

This update for containerd, docker, runc fixes the following issues:

• Docker was updated to 20.10.6-ce

  • Switch version to use -ce suffix rather than _ce to avoid confusing other tools (bsc#1182476).
  • CVE-2021-21284: Fixed a potential privilege escalation when the root user in the remapped namespace has access to the host filesystem (bsc#1181732)
  • CVE-2021-21285: Fixed an issue where pulling a malformed Docker image manifest crashes the dockerd daemon (bsc#1181730).

• runc was updated to v1.0.0~rc93 (bsc#1182451 and bsc#1184962).

  • Use the upstream runc package (bsc#1181641, bsc#1181677, bsc#1175821).
  • Fixed /dev/null is not available (bsc#1168481).
  • Fixed an issue where podman hangs when spawned by salt-minion process (bsc#1149954).
  • CVE-2019-19921: Fixed a race condition with shared mounts (bsc#1160452).
  • CVE-2019-16884: Fixed an LSM bypass via malicious Docker image that mount over a /proc directory (bsc#1152308).
  • CVE-2019-5736: Fixed potential write attacks to the host runc binary (bsc#1121967).
  • Fixed an issue where after a kernel-update docker doesn't run (bsc#1131314 bsc#1131553)
  • Ensure that we always include the version information in runc (bsc#1053532).

• Switch to Go 1.13 for build.

  • CVE-2018-16873: Fixed a potential remote code execution (bsc#1118897).
  • CVE-2018-16874: Fixed a directory traversal in 'go get' via curly braces in import paths (bsc#1118898).
  • CVE-2018-16875: Fixed a CPU denial of service (bsc#1118899).
  • Fixed an issue with building containers (bsc#1095817).

• containerd was updated to v1.4.4

  • CVE-2021-21334: Fixed a potential information leak through environment variables (bsc#1183397).
  • Handle a requirement from docker (bsc#1181594).
  • Install the containerd-shim* binaries and stop creating (bsc#1183024).
  • update version to the one required by docker (bsc#1034053)

• Use -buildmode=pie for tests and binary build (bsc#1048046, bsc#1051429)

• Cleanup seccomp builds similar (bsc#1028638).

• Update to handle the docker-runc removal, and drop the -kubic flavour (bsc#1181677, bsc#1181749)

This update for containerd, docker, runc fixes the following issues:

Docker was updated to 20.10.6-ce (bsc#1184768, bsc#1182947, bsc#1181594)

• Switch version to use -ce suffix rather than _ce to avoid confusing other tools (bsc#1182476).
• CVE-2021-21284: Fixed a potential privilege escalation when the root user in the remapped namespace has access to the host filesystem (bsc#1181732)
• CVE-2021-21285: Fixed an issue where pulling a malformed Docker image manifest crashes the dockerd daemon (bsc#1181730).
• btrfs quotas being removed by Docker regularly (bsc#1183855, bsc#1175081)

runc was updated to v1.0.0~rc93 (bsc#1182451, bsc#1175821 bsc#1184962).

• Use the upstream runc package (bsc#1181641, bsc#1181677, bsc#1175821).
• Fixed /dev/null is not available (bsc#1168481).
• CVE-2021-30465: Fixed a symlink-exchange attack vulnarability (bsc#1185405).

containerd was updated to v1.4.4

• CVE-2021-21334: Fixed a potential information leak through environment variables (bsc#1183397).
• Handle a requirement from docker (bsc#1181594).

This update for docker-stable fixes the following issues:

• Include historical changelog data from before the docker-stable fork. The initial changelog entry did technically provide all the necessary information, but our CVE tracking tools do not understand how the package is forked and so it seems that this package does not include fixes for ~12 years of updates. So, include a copy of the original package's changelog up until the fork point. (bsc#1250596)

• Remove git-core recommends on SLE. Most SLE systems have installRecommends=yes by default and thus end up installing git with Docker. bsc#1250508

  This feature is mostly intended for developers ('docker build git://') so most users already have the dependency installed, and the error when git is missing is fairly straightforward (so they can easily figure out what they need to install).

• Backport https://github.com/moby/moby/pull/48517. bsc#1247362

• Update to docker-buildx v0.25.0. Upstream changelog: https://github.com/docker/buildx/releases/tag/v0.25.0

• Do not try to inject SUSEConnect secrets when in Rootless Docker mode, as Docker does not have permission to access the host zypper credentials in this mode (and unprivileged users cannot disable the feature using /etc/docker/suse-secrets-enable.) bsc#1240150

• Initial docker-stable fork, forked from Docker 24.0.7-ce release (packaged on 2024-02-14). The original changelog is included below for historical reference.

This update for docker-stable fixes the following issues:

Note this update contains a already fixed references mostly.

• Remove git-core recommends on SLE to avoid pulling it in unnecessary. (bsc#1250508)

  This feature is mostly intended for developers ('docker build git://') so most users already have the dependency installed, and the error when git is missing is fairly straightforward (so they can easily figure out what they need to install).

• Include historical changelog data from before the docker-stable fork. The initial changelog entry did technically provide all the necessary information, but our CVE tracking tools do not understand how the package is forked and so it seems that this package does not include fixes for ~12 years of updates. So, include a copy of the original package's changelog up until the fork point. bsc#1250596

• Update to docker-buildx v0.25.0. Upstream changelog: https://github.com/docker/buildx/releases/tag/v0.25.0

• Update to Go 1.23 for building now that upstream has switched their 23.0.x LTSS to use Go 1.23.

• Do not try to inject SUSEConnect secrets when in Rootless Docker mode, as Docker does not have permission to access the host zypper credentials in this mode (and unprivileged users cannot disable the feature using /etc/docker/suse-secrets-enable.) bsc#1240150

• Initial docker-stable fork, forked from Docker 24.0.7-ce release (packaged on 2024-02-14). The original changelog is included below for historical reference.