CVE-2026-19820: CWE-59 Improper Link Resolution Before File Access in Backblaze Backblaze Client
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.
CVE-2026-19820: CWE-59 Improper Link Resolution Before File Access in Backblaze Backblaze Client
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.
CVSS v4.0
Score 5.8medium
Affected software
Weaknesses
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Bugcrowd
- Date Reserved
- 2026-08-14T05:28:19.979Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a961e58acd9273b49c90e95
Added to database: 09/01/2026, 00:37:44 UTC
Last updated: 09/01/2026, 02:52:31 UTC
Views: 6
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