Path Traversal in Shaneisrael Fireshare
CVE-2026-33645
Fireshare facilitates self-hosted media and link sharing. In version 1.5.1, an authenticated path traversal vulnerability in Fireshare’s chunked upload endpoint allows an attacker to write arbitrary files outside the intended upload directory. The `checkSum` multipart field is used directly in filesystem path construction without sanitization or containment checks. This enables unauthorized file writes to attacker-chosen paths writable by the Fireshare process (e.g., container `/tmp`), violating integrity and potentially enabling follow-on attacks depending on deployment. Version 1.5.2 fixes the issue.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L.
EPSS exploit prediction
EPSS: 0.005 (43.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001
Affected products
- Shaneisrael Fireshare — versions 1.5.1, = 1.5.2
Weakness classification (CWE)
References
- github.com/ShaneIsrael/fireshare/security/advisories/GHSA-7q8r-vpq3-89m7 (Vendor Advisory)
- github.com/ShaneIsrael/fireshare/releases/tag/v1.5.2 (Release Notes)
Frequently asked questions
- What is CVE-2026-33645?
- CVE-2026-33645 is a high-severity vulnerability in Shaneisrael Fireshare, classified under Path Traversal. CVSS score: 7.1/10. Published 2026-03-26.
- How severe is CVE-2026-33645?
- High severity. CVSS v3 base score is 7.1 out of 10.