CVE Catalog

CVE-2026-19820

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.33%

26th percentile - higher than 26% of all known CVEs

Summary

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.

Risk Assessment

A local attacker with administrator privileges can cause a system crash, preventing boot, leading to downtime and potential data loss.

Recommendation

Apply Windows security updates and restrict access to the Backblaze folder to prevent creation of dangerous links.

Related vulnerabilities

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS