CVE-2025-3445: A Path Traversal "Zip Slip" vulnerability has been identified in mholt/archiver in Go.

A Path Traversal "Zip Slip" vulnerability has been identified in mholt/archiver in Go.

A Path Traversal "Zip Slip" vulnerability has been identified in mholt/archiver in Go. This vulnerability allows using a crafted ZIP file containing path traversal symlinks to create or overwrite files with the user's privileges or application utilizing the library. When using the archiver.Unarchive functionality with ZIP files, like this: archiver.Unarchive(zipFile, outputDir), A crafted ZIP file can be extracted in such a way that it writes files to the affected system with the same privileges as the application executing this vulnerable functionality. Consequently, sensitive files may be overwritten, potentially leading to privilege escalation, code execution, and other severe outcomes in some cases. It's worth noting that a similar vulnerability was found in TAR files (CVE-2024-0406). Although a fix was implemented, it hasn't been officially released, and the affected project has since been deprecated. The successor to mholt/archiver is a new project called mholt/archives, and its initial release (v0.1.0) removes the Unarchive() functionality.

Description from the National Vulnerability Database, published by reefs@jfrog.com

What it means for a small business

If your business uses github.com/mholt/archiver/v3, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.51%, higher than 43% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 28, 2026, updated daily.

Check your own setup

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Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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