# CVE-2026-116073: Leon before commit 50df142 Path Traversal via /download model Command

Status: published. Published: 2026-10-25. Updated: 2026-11-05.

Leon before commit 50df142 contains a path traversal vulnerability in getModelFileNameFromURL() that allows attackers to write files outside the models directory via percent-encoded separators. Attackers can trick a user into running '/download model' with a crafted URL containing encoded '../' sequences to write attacker-controlled content to arbitrary paths writable by Leon.

## 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/leon-ai/leon/pull/594
- 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/leon-ai/leon/commit/50df142a89a0859e5b7283d87afdab7b01e712a2

## Affected products and versions

- leon-ai / leon: ≥ a3afdef81c8dd085b922f5a4e6b68bb9b9d802e4; < 50df142a89a0859e5b7283d87afdab7b01e712a2 (affected, git). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 6.9 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N; source: CNA: VulnCheck

- CVSS 4.0: 6.9 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/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: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: 0.33% as of 2026-11-05; percentile 25.69%

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

- Weaknesses: CWE-22

## Exploit evidence

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

## References

- https://github.com/leon-ai/leon/issues/593 (CNA: VulnCheck; issue-tracking)

- https://github.com/leon-ai/leon (CNA: VulnCheck; product)

- https://github.com/leon-ai/leon/blob/21baf11714f618a9367f25882e59e856d3308037/server/src/built-in-command/commands/download-command/download-command.ts#L21-L28 (CNA: VulnCheck; technical-description)

- https://github.com/leon-ai/leon/pull/594 (CNA: VulnCheck; patch, issue-tracking)

- https://github.com/leon-ai/leon/commit/50df142a89a0859e5b7283d87afdab7b01e712a2 (CNA: VulnCheck; patch)

- https://www.vulncheck.com/advisories/leon-before-commit-50df142-path-traversal-via-download-model-command (CNA: VulnCheck; third-party-advisory)

- https://github.com/leon-ai/leon (disclosure@vulncheck.com)

- https://github.com/leon-ai/leon/blob/21baf11714f618a9367f25882e59e856d3308037/server/src/built-in-command/commands/download-command/download-command.ts#L21-L28 (disclosure@vulncheck.com)

- https://github.com/leon-ai/leon/commit/50df142a89a0859e5b7283d87afdab7b01e712a2 (disclosure@vulncheck.com)

- https://github.com/leon-ai/leon/issues/593 (disclosure@vulncheck.com)

- https://github.com/leon-ai/leon/pull/594 (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/leon-before-commit-50df142-path-traversal-via-download-model-command (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-116073; retrieved 2026-11-05; source updated 2026-11-05

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-116073; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-116073; retrieved 2026-11-05; source updated Not reported

Revision: 9d958fc9dc5264799089e1b30641c261742c529fc8db2d40f0a201b892bd50f3

Canonical: https://y2.dev/cve/CVE-2026-116073

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