# CVE-2026-121546: ruTorrent before 5.3.20 Path Traversal via datadir Plugin Symlink Following

Status: published. Published: 2026-11-03. Updated: 2026-11-09.

ruTorrent before 5.3.20 contains a path traversal vulnerability in the datadir plugin that allows authenticated users to escape the topDirectory jail because correctDirectory() does not resolve symbolic links. Attackers can submit a datadir path through a symlink under their top directory to create directories and move torrent data to locations writable by the web server or rtorrent.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/Novik/ruTorrent/commit/2059ff12464b2ce14fd0f53df8d6b19fb6b8a5eb

## Affected products and versions

- Novik / ruTorrent: ≥ 0; < 5.3.20 (affected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 6 (medium); CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 5.9 (medium); CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L; source: CNA: VulnCheck

- CVSS 4.0: 6 (medium); CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: disclosure@vulncheck.com

- CVSS 3.1: 5.9 (medium); CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: 0.40% as of 2026-11-09; percentile 34.69%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-59

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/Novik/ruTorrent/issues/3474 (CNA: VulnCheck; issue-tracking)

- https://github.com/Novik/ruTorrent (CNA: VulnCheck; product)

- https://github.com/Novik/ruTorrent/commit/2059ff12464b2ce14fd0f53df8d6b19fb6b8a5eb (CNA: VulnCheck; patch)

- https://github.com/Novik/ruTorrent/blob/v5.3.19/plugins/datadir/action.php#L60 (CNA: VulnCheck; technical-description)

- https://github.com/Novik/ruTorrent/blob/v5.3.19/php/settings.php#L526-L541 (CNA: VulnCheck; technical-description)

- https://www.vulncheck.com/advisories/rutorrent-before-5.3.20-path-traversal-via-datadir-plugin-symlink-following (CNA: VulnCheck; third-party-advisory)

- https://github.com/Novik/ruTorrent (disclosure@vulncheck.com)

- https://github.com/Novik/ruTorrent/blob/v5.3.19/php/settings.php#L526-L541 (disclosure@vulncheck.com)

- https://github.com/Novik/ruTorrent/blob/v5.3.19/plugins/datadir/action.php#L60 (disclosure@vulncheck.com)

- https://github.com/Novik/ruTorrent/commit/2059ff12464b2ce14fd0f53df8d6b19fb6b8a5eb (disclosure@vulncheck.com)

- https://github.com/Novik/ruTorrent/issues/3474 (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/rutorrent-before-5.3.20-path-traversal-via-datadir-plugin-symlink-following (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-121546; retrieved 2026-11-09; source updated 2026-11-09

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-121546; retrieved 2026-11-03; source updated 2026-11-03

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-121546; retrieved 2026-11-09; source updated Not reported

Revision: 0146558d6840e0a26839e1a9efdf8981a84d43f389186554d0ca5849d0682998

Canonical: https://y2.dev/cve/CVE-2026-121546

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