CVE-2026-19820
Backblaze Client for Windows Improper Link Resolution Vulnerability
- State
- Published
- Severity
- 5.8 Medium
- Published
- Sep 1, 2026
- Updated
- Sep 10, 2026
- Reserved
- Aug 14, 2026
Description
A vulnerability in the Backblaze Client allows a local user to make the system not bootable by creating a link from Backblaze's folder to Windows OS system files during a backup. Successful exploitation requires an administrator-level system change that results in the absence of specific Windows OS security controls. This vulnerability is due to improper link resolution.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.8 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:L/SA:L | Bugcrowd |
Weaknesses
- CWE-59 Improper Link Resolution Before File Access ('Link Following')
Affected Products
| Product | Versions |
|---|---|
Backblaze ClientBackblaze |
|
References
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