CVE-2025-67487

Static Web Server (SWS) is a production-ready web server suitable for static web files or assets. Versions 2.40.0 and below contain symbolic links (symlinks) which can be used to access files or directories outside the intended web root folder. SWS generally does not prevent symlinks from escaping the web server’s root directory. Therefore, if a malicious actor gains access to the web server’s root directory, they could create symlinks to access other files outside the designated web root folder either by URL or via the directory listing. This issue is fixed in version 2.40.1.

Weakness

The product, when opening a file or directory, does not sufficiently account for when the file is a symbolic link that resolves to a target outside of the intended control sphere. This could allow an attacker to cause the product to operate on unauthorized files.

Affected Software

Potential Mitigations

• Follow the principle of least privilege when assigning access rights to entities in a software system.
• Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/27.html

References

• https://github.com/static-web-server/static-web-server/commit/308f0d26ceb9c2c8bd219315d0f53914763357f2
• https://github.com/static-web-server/static-web-server/security/advisories/GHSA-459f-x8vq-xjjm
• https://github.com/static-web-server/static-web-server/security/advisories/GHSA-459f-x8vq-xjjm