Vulnerability · Published Aug 25, 2026 · Assigned by VulnCheck
CVE-2026-80189LeafWiki 0.10.0 through 0.12.0 Uncontrolled Resource Consumption via Unbounded ZIP Extraction
Medium 6.5
In plain English
A medium-severity security flaw in leafwiki from perber. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 46% of all known vulnerabilities).
Official description
LeafWiki extracts an uploaded ZIP archive without limiting how much data it will write. ZipExtractor.ExtractToDir in internal/importer/zip_extractor.go opens each entry and copies it to the destination with io.Copy, which runs to the end of the decompressed stream, so only the size of the uploaded archive is bounded and the size it expands to is not. The import route that reaches this code requires the Editor or Admin role, and the upload itself is capped at 500 MiB compressed. Because a ZIP entry can compress at a very high ratio, an archive well inside that cap can expand to hundreds of gigabytes as it is written out. The extraction directory defaults to a location under the operating system temporary directory, so the written data consumes the disk backing that path, which on a tmpfs-backed temporary directory is memory. A user holding the Editor role can therefore exhaust the storage the service depends on and keep it from serving, using far more resource than the upload limit alone would permit.
Affected products (as reported)
Weakness: CWE-409 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/perber/leafwiki product
- GitHub Security Advisory (GHSA-258m-crqp-25xc) vendor-advisory
- https://github.com/perber/leafwiki/blob/v0.12.0/internal/importer/zip_extractor.go technical-description
- LeafWiki v0.12.1 Release Notes release-notes
- VulnCheck Advisory: LeafWiki 0.10.0 through 0.12.0 Uncontrolled Resource Consumption via Unbounded ZIP Extraction third-party-advisory