CVE-2026-19820
High
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.
SeverityHigh
CVSS7.8
Exploit probability—
ProductBackblaze Client
PublishedSep 1, 2026
First seenSep 1, 2026
Weakness typeCWE-59Improper link resolution
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Backblaze Backblaze Client | 10.0.0.1029, 10.0.1.1037, 10.0.2.1047 | — |
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