CVE-2026-33645 (GCVE-0-2026-33645)

Vulnerability from cvelistv5 – Published: 2026-03-26 20:58 – Updated: 2026-03-27 20:01
VLAI
Title
Fireshare has Path Traversal Arbitrary File Write in `/api/uploadChunked`
Summary
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.
Severity
7.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-27 14:30 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-73 - External Control of File Name or Path
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
ShaneIsrael fireshare Affected: = 1.5.2
Create a notification for this product.
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