CVE-2026-72567: DeepWiki Path Traversal Vulnerability

CVE-2026-72567 Overview

CVE-2026-72567 is a path traversal vulnerability in AsyncFuncAI deepwiki-open through commit 16f35a0. The wiki-cache endpoint in api/api.py constructs file paths from user-controlled owner, repo, and repo_type fields without sanitization. Unauthenticated remote attackers can write to or delete arbitrary files with root privileges on the host running the application. The flaw maps to [CWE-22] (Improper Limitation of a Pathname to a Restricted Directory).

Critical Impact
Remote, unauthenticated attackers can overwrite or delete any file writable by the deepwiki-open process, including system binaries, configuration files, and application data.

Affected Products

AsyncFuncAI deepwiki-open through commit 16f35a0
The api/api.pywiki-cache endpoint
Deployments running the service with root privileges

Discovery Timeline

2026-08-10 - CVE-2026-72567 published to NVD
2026-08-10 - Last updated in NVD database

Technical Details for CVE-2026-72567

Vulnerability Analysis

The deepwiki-open API exposes a wiki-cache endpoint that persists cached wiki content to disk. The handler builds destination paths by concatenating attacker-controlled request fields, owner, repo, and repo_type, directly into a filesystem path. No canonicalization or allowlist check confirms that the resulting path resides within the intended cache directory.

Because the endpoint accepts requests without authentication, any network-reachable client can submit crafted values containing ../ sequences or absolute paths. The service then performs write or delete operations at the attacker-selected location. When the process runs as root, which is the default in the referenced container configuration, the impact extends to any file on the host.

Root Cause

The root cause is missing input validation on the owner, repo, and repo_type fields consumed by the wiki-cache handler in api/api.py. The code trusts user input for path construction and does not enforce a base-directory boundary using functions such as os.path.realpath or Path.resolve() combined with a containment check.

Attack Vector

An attacker sends an HTTP request to the wiki-cache endpoint with traversal payloads embedded in the owner, repo, or repo_type parameters. Values such as ../../../../etc/cron.d/pwn redirect the write operation outside the cache directory. Delete operations exposed by the same endpoint can be abused to remove critical system files, producing denial of service or enabling privilege manipulation when combined with a write primitive.

No authentication, user interaction, or prior privileges are required. Refer to the GitHub DeepWiki API Implementation for the vulnerable code path.

Detection Methods for CVE-2026-72567

Indicators of Compromise

HTTP requests to the wiki-cache endpoint containing .., %2e%2e, or absolute path prefixes such as /etc/, /root/, or /var/ in the owner, repo, or repo_type fields.
Unexpected file creation, modification, or deletion by the deepwiki-open process outside its designated cache directory.
New or altered files in sensitive locations such as /etc/cron.d/, /root/.ssh/authorized_keys, or SUID binaries with timestamps matching deepwiki-open activity.

Detection Strategies

Inspect reverse proxy and application logs for wiki-cache requests with traversal sequences or unusual character encodings in path parameters.
Correlate deepwiki-open process file operations with the intended cache directory and alert on writes to paths outside that scope.
Monitor for anomalous outbound connections or persistence artifacts appearing shortly after wiki-cache requests.

Monitoring Recommendations

Enable file integrity monitoring on the host for system directories and the application configuration tree.
Ship application, web server, and audit logs to a centralized platform and build alerts on path-traversal signatures.
Track process lineage for children spawned by the deepwiki-open service to catch post-exploitation activity such as shell execution.

How to Mitigate CVE-2026-72567

Immediate Actions Required

Restrict network exposure of the deepwiki-open service to trusted networks or place it behind an authenticated reverse proxy immediately.
Stop running the service as root; drop privileges to a dedicated low-privilege user with write access limited to the cache directory.
Audit the cache directory and host filesystem for unauthorized writes or deletions since deployment.

Patch Information

At the time of publication, no fixed release is referenced in the NVD entry. Track the GitHub Repository for DeepWiki for commits addressing path validation in the wiki-cache handler and apply them once available.

Workarounds

Deploy a reverse proxy rule that rejects requests to /wiki-cache containing .., encoded traversal sequences, or path separators inside the owner, repo, and repo_type fields.
Run the container as a non-root user and mount the cache directory as the only writable path using a read-only root filesystem.
Apply a local patch that validates each user-supplied path component against a strict allowlist regex such as ^[A-Za-z0-9_.-]+$ before path construction.

bash

# Example: run the container as non-root with a read-only root filesystem
docker run \
  --read-only \
  --user 10001:10001 \
  --tmpfs /tmp \
  -v /srv/deepwiki/cache:/app/cache \
  -p 127.0.0.1:8000:8000 \
  deepwiki-open:latest