Vulnerability · Published Apr 6, 2026 · Assigned by GitHub_M

CVE-2026-34783Ferret has a Path Traversal in IO::FS::WRITE allows arbitrary file write when scraping malicious websites

High 8.1

In plain English

A high-severity path traversal in ferret from MontFerret. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.1High
Exploit odds (30 days)0.5%top 55.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Gogithub.com/MontFerret/ferretno fix listedGHSA-j6v5-g24h-vg4j
Gogithub.com/MontFerret/ferret/v22.0.0-alpha.4GHSA-j6v5-g24h-vg4j
Gogithub.com/MontFerret/ferret/v22.0.0-alpha.4GO-2026-5452

Affected products (as reported)

VendorProductVersions
MontFerret ferret < 2.0.0-alpha.4

Weakness: CWE-22, CWE-73 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H

References