CVE-2026-80189 LeafWiki 0.10.0 through 0.12.0 Uncontrolled Resource Consumption via Unbounded ZIP Extraction
An Editor can cause denial of service by uploading a highly compressed ZIP file that exhausts disk or memory resources during extraction.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-80189?
CVE-2026-80189 is a high-severity denial of service vulnerability in perber leafwiki, published on 25 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
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.
Weakness: CWE-409
Which versions are affected by CVE-2026-80189?
How do I fix CVE-2026-80189?
No fix has been published for CVE-2026-80189 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-80189 being exploited?
There is no known exploitation of CVE-2026-80189 in the wild and no public exploit code.
Sources
Also known as GHSA-258m-crqp-25xc, GHSA-vx6x-47wx-xjjj.