high CVSS 8.1

CVE-2026-33588·Docker vulnerability

Lack of user input validation in the file upload functionality of Open Notebook v1.8.3 allows the application user to create or modify files on the docker container via path traversal.

Severity
high
Software
Docker
Fixed in
1.8.4
Published
2026-05-07

Affected versions

Until: 1.8.4

Fixed in: 1.8.4

How to fix this CVE

Upgrade Docker to version 1.8.4 or later to patch the path traversal vulnerability in file upload handling. This update addresses insufficient input validation that could allow authenticated users to read, write, or modify arbitrary files within the container filesystem. Apply the update immediately to all Docker installations, especially those exposed to untrusted users.

sudo dnf update docker-ce

Defensia detects this vulnerability

WAF mitigation (if patching is not yet possible)

Add this rule to your WAF to block exploitation attempts while you schedule the patch. 

Implement WAF rules to block HTTP requests containing path traversal sequences (e.g., '../', '..\', '%2e%2e%2f') in file upload endpoints; enforce strict input validation on all file path parameters and limit uploads to a whitelist of allowed directories.

How to check if you are affected

  1. Check installed Docker version: docker --version or docker info | grep 'Server Version'
  2. Verify if the vulnerable file upload functionality is in use by checking Docker Compose configurations and mounted volumes for user-facing file operations
  3. Review container logs for suspicious file path patterns containing '../' or absolute path references: docker logs <container_id> | grep -E '(\.\./|/etc/|/root/|/var/)'
  4. Confirm the patch: Compare the running Docker version against version 1.8.4 to ensure the update was applied successfully

FAQ

What is CVE-2026-33588?

CVE-2026-33588 is a path traversal vulnerability in Docker's file upload functionality that fails to properly validate user input, allowing authenticated attackers to create, modify, or read files outside the intended directory within the container.

Is CVE-2026-33588 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog and no public exploits are currently available, though the high CVSS score (8.1) warrants prompt remediation.

What versions of Docker are affected by CVE-2026-33588?

All versions up to and including Docker 1.8.3 are affected; version 1.8.4 and later contain the fix.

How do I check if my server is vulnerable to CVE-2026-33588?

Run 'docker --version' and compare the version number; if it is 1.8.3 or earlier, the system is vulnerable and requires immediate patching.

Does Defensia detect CVE-2026-33588?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Docker is installed on a monitored server, CVE-2026-33588 will appear in your dashboard with remediation steps.

Related Docker CVEs

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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.
CVE-2026-26216CVSS 10Crawl4AI versions prior to 0.8.0 contain a remote code execution vulnerability in the Docker API deployment. The /crawl endpoint accepts a hooks parameter containing Python code that is executed using exec(). The __import__ builtin was included in the allowed builtins, allowing unauthenticated remote attackers to import arbitrary modules and execute system commands. Successful exploitation allows full server compromise, including arbitrary command execution, file read and write access, sensitive data exfiltration, and lateral movement within internal networks.
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.
CVE-2026-33587CVSS 10Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and subsequently OS commands) on the docker container via Server-Side Template Injection (SSTI) for user-created transformations.

References

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