CVE-2025-54388

Moby is an open source container framework developed by Docker Inc. that is distributed as Docker Engine, Mirantis Container Runtime, and various other downstream projects/products. The Moby daemon component (dockerd), which is developed as moby/moby is commonly referred to as Docker, or Docker Engine.

Firewalld is a daemon used by some Linux distributions to provide a dynamically managed firewall. When Firewalld is running, Docker uses its iptables backend to create rules, including rules to isolate containers in one bridge network from containers in other bridge networks.

Workarounds

After reloading firewalld, either:

• Restart the docker daemon,
• Re-create bridge networks, or
• Use rootless mode.

References

https://firewalld.org/
https://firewalld.org/documentation/howto/reload-firewalld.html

The iptables rules created by Docker are removed when firewalld is reloaded using, for example "firewall-cmd --reload", "killall -HUP firewalld", or "systemctl reload firewalld".

When that happens, Docker must re-create the rules. However, in affected versions of Docker, the iptables rules that prevent packets arriving on a host interface from reaching container addresses are not re-created.

Once these rules have been removed, a remote host configured with a route to a Docker bridge network can access published ports, even when those ports were only published to a loopback address. Unpublished ports remain inaccessible.

For example, following a firewalld reload on a Docker host with address 192.168.0.10 and a bridge network with subnet 172.17.0.0/16, running the following command on another host in the local network will give it access to published ports on container addresses in that network: ip route add 172.17.0.0/16 via 192.168.0.10.

Containers running in networks created with --internal or equivalent have no access to other networks. Containers that are only connected to these networks remain isolated after a firewalld reload.

Where Docker Engine is not running in the host's network namespace, it is unaffected. Including, for example, Rootless Mode, and Docker Desktop.

CVE-2025-54388 has a CVSS score of 4.6 (Medium). The vector is reachable from an adjacent network, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (28.3.3); upgrading removes the vulnerable code path.

Kodem intelligence

Moby releases older than 28.2.0 are not affected. A fix is available in moby release 28.3.3.

1. What is CVE-2025-54388? CVE-2025-54388 is a medium-severity security vulnerability in github.com/docker/docker (go), affecting versions >= 28.2.0, < 28.3.3. It is fixed in 28.3.3.
2. How severe is CVE-2025-54388? CVE-2025-54388 has a CVSS score of 4.6 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of github.com/docker/docker are affected by CVE-2025-54388? github.com/docker/docker (go) versions >= 28.2.0, < 28.3.3 is affected.
4. Is there a fix for CVE-2025-54388? Yes. CVE-2025-54388 is fixed in 28.3.3. Upgrade to this version or later.
5. Is CVE-2025-54388 exploitable, and should I be worried? Whether CVE-2025-54388 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2025-54388 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2025-54388? Upgrade github.com/docker/docker to 28.3.3 or later.