CVE-2026-34783

Ferret has a Path Traversal in IO::FS::WRITE allows arbitrary file write when scraping malicious websites

State: Published
Severity: 8.1 High
Published: Apr 6, 2026
Updated: Apr 7, 2026
Reserved: Mar 30, 2026

Description

Ferret is a declarative system for working with web data. Prior to 2.0.0-alpha.4, a path traversal vulnerability in Ferret's IO::FS::WRITE standard library function allows a malicious website to write arbitrary files to the filesystem of the machine running Ferret. When an operator scrapes a website that returns filenames containing ../ sequences, and uses those filenames to construct output paths (a standard scraping pattern), the attacker controls both the destination path and the file content. This can lead to remote code execution via cron jobs, SSH authorized_keys, shell profiles, or web shells. This vulnerability is fixed in 2.0.0-alpha.4.

Scores

CVSS	Score	Vector	Source
3.1	8.1 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H	GitHub_M

Weaknesses

CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CWE-73 External Control of File Name or Path

Affected Products

Product	Versions
ferretMontFerret	< 2.0.0-alpha.4Affected

References

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