Vulnerability Description
ApostropheCMS is an open-source content management framework. Prior to version 3.5.3 of `@apostrophecms/import-export`, The `extract()` function in `gzip.js` constructs file-write paths using `fs.createWriteStream(path.join(exportPath, header.name))`. `path.join()` does not resolve or sanitise traversal segments such as `../`. It concatenates them as-is, meaning a tar entry named `../../evil.js` resolves to a path outside the intended extraction directory. No canonical-path check is performed before the write stream is opened. This is a textbook Zip Slip vulnerability. Any user who has been granted the Global Content Modify permission — a role routinely assigned to content editors and site managers — can upload a crafted `.tar.gz` file through the standard CMS import UI and write attacker-controlled content to any path the Node.js process can reach on the host filesystem. Version 3.5.3 of `@apostrophecms/import-export` fixes the issue.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Apostrophecms | Import-Export | < 3.5.3 |
Related Weaknesses (CWE)
References
- https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-mwxc-m426-3ExploitVendor Advisory
FAQ
What is CVE-2026-32731?
CVE-2026-32731 is a vulnerability with a CVSS score of 9.9 (CRITICAL). ApostropheCMS is an open-source content management framework. Prior to version 3.5.3 of `@apostrophecms/import-export`, The `extract()` function in `gzip.js` constructs file-write paths using `fs.crea...
How severe is CVE-2026-32731?
CVE-2026-32731 has been rated CRITICAL with a CVSS base score of 9.9/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-32731?
Check the references section above for vendor advisories and patch information. Affected products include: Apostrophecms Import-Export.