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TI-2026-26989 Aliases CVE-2026-34745

Unauthenticated Path Traversal Arbitrary File Write in /api/uploadChunked/public

Priority HIGH 78CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Fireshare facilitates self-hosted media and link sharing. Prior to version 1.5.3, the fix for CVE-2026-33645 was applied to the authenticated /api/uploadChunked endpoint but was not applied to the unauthenticated /api/uploadChunked/public endpoint in the same file (app/server/fireshare/api.py). An unauthenticated attacker can exploit the checkSum parameter to write arbitrary files with attacker-controlled content to any writable path on the server filesystem. This issue has been patched in version 1.5.3.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00632 50th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed fireshare (ShaneIsrael): 1.5.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ShaneIsraelfiresharebefore 1.5.31.5.3Patch availableCNA
  • fireshare VendorShaneIsrael Affected before 1.5.3 Fixed in 1.5.3 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:shaneisrael:fireshare:*:*:*:*:*:*:*:*before 1.5.3VulnerableShaneIsrael
  • cpe:2.3:a:shaneisrael:fireshare:*:*:*:*:*:*:*:* Versions before 1.5.3 Vulnerable ·ShaneIsrael

Remediation

  • Fix · CNA fireshare (ShaneIsrael) Fixed in 1.5.3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-34745
  2. 2026-10-25 EPSS moved to the below the 50th percentile
  3. 2026-10-30 EPSS moved to the 50th–90th percentile

References

Exploit 1

Patch 2

Other 1

  • TI-2026-26026 Fireshare has Path Traversal Arbitrary File Write in `/api/uploadChunked` CVSS 3.1HIGH 8.1
  • TI-2025-35020 FireShare FileShare 1.2.25 contains a time-based blind SQL injection vulnerability in the… CVSS 3.1MEDIUM 6.5
  • TI-2025-41424 Fireshare Public Uploads feature is vulnerable to OS Command Injection (RCE) CVSS 3.1CRITICAL 9.8

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences