high CVSS 8.2

CVE-2026-5843·Docker vulnerability

The MLX inference backend in Docker Model Runner on macOS uses the MLX-LM library, which unconditionally imports and executes arbitrary Python files from model directories via the model_file configuration field in config.json. When a model's config.json specifies a model_file pointing to a Python file, MLX-LM uses importlib to load and execute it with no trust_remote_code gate or equivalent safety check. The MLX backend runs without sandboxing, resulting in arbitrary code execution on the Docker host as the Docker Desktop user. Any container on the Docker network can trigger this by calling the model-runner.docker.internal API to pull a malicious model from an attacker-controlled OCI registry and request inference.

Severity
high
Software
Docker
Fixed in
4.71.0
Published
2026-05-22

Affected versions

From: 4.56.0

Until: 4.71.0

Fixed in: 4.71.0

How to fix this CVE

Update Docker Desktop to version 4.71.0 or later to patch the unsafe Python code execution vulnerability in the MLX inference backend. The vulnerability allows containers to trigger arbitrary code execution on the host system by loading malicious models from untrusted registries. Immediately upgrade all affected Docker installations, particularly those running Docker Model Runner on macOS with network-accessible inference APIs.

sudo dnf update docker-ce docker-ce-cli --assumeyes

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check Docker version with `docker --version` and compare against 4.56.0–4.70.1 range to identify vulnerable installations
  2. Step 2: Verify if Model Runner is enabled by checking for docker-compose files or configuration mounting `/var/run/model-runner.docker.internal` socket
  3. Step 3: Search Docker daemon logs for model-runner API calls: `grep -i 'model-runner\|model_file' /var/lib/docker/containers/*/config.v2.json or journalctl -u docker -g model-runner`
  4. Step 4: Confirm successful remediation by running `docker --version` and verifying the version is 4.71.0 or later

FAQ

What is CVE-2026-5843?

CVE-2026-5843 is a code execution vulnerability in Docker's MLX inference backend that fails to validate Python files before loading them from model configurations, allowing attackers to execute arbitrary code on the Docker host system.

Is CVE-2026-5843 being actively exploited?

No, CVE-2026-5843 is not currently listed in CISA's Known Exploited Vulnerabilities catalog and has no public exploits available, but the attack surface is significant for organizations running untrusted containerized workloads.

What versions of Docker are affected by CVE-2026-5843?

Docker versions 4.56.0 through 4.70.1 are affected; users should upgrade to 4.71.0 or later to receive the fix.

How do I check if my server is vulnerable to CVE-2026-5843?

Run `docker --version` and check if the version falls between 4.56.0 and 4.70.1. Additionally, verify Model Runner is active by checking if the inference socket is listening with `ls -la /var/run/model-runner.docker.internal 2>/dev/null`.

Does Defensia detect CVE-2026-5843?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Docker is installed on a monitored server, CVE-2026-5843 will appear in your dashboard with remediation steps.

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CVE-2026-53576CVSS 10Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, the authentication filter for the REST API (@Filter("/api/v1/**")) treats any request whose path ends in /configs as the public instance-config endpoint and forwards it without a credential check. kestra addresses its resources by URL path segments that the caller chooses (/api/v1/{tenant}/flows/{namespace}, /api/v1/{tenant}/executions/{namespace}/{id}, /api/v1/{tenant}/namespaces/{namespace}/kv/{key}). An anonymous caller picks the literal configs as the final segment, and the request bypasses Basic-Auth entirely. Because the bypass reaches the flow-create and execution-trigger routes, an unauthenticated caller creates a flow containing a Shell or Process task and runs it. The task executes as root inside the kestra container. The official docker-compose.yml mounts /var/run/docker.sock, so root in the container reaches the host Docker daemon. This vulnerability is fixed in 1.0.45 and 1.3.21.
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CVE-2026-44329CVSS 10free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without OAuth2/bearer-token authorization middleware. A network attacker who can reach SMF on the SBI can hit UPI endpoints with no Authorization header at all, and the requests reach the SMF business handlers. In the running Docker lab this was directly demonstrated for read (GET /upi/v1/upNodesLinks), write (POST /upi/v1/upNodesLinks with attacker-controlled UP-node and link payload), and delete (DELETE /upi/v1/upNodesLinks/{nodeID}) operations. This vulnerability is fixed in 4.2.2.
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References

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