CVE-2025-68435: Zerobyte has Authentication Bypass by Primary Weakness

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-12-17 · updated 2026-06-17
Weakness: CWE-305

Description

Zerobyte is a backup automation tool Zerobyte versions prior to 0.18.5 and 0.19.0 contain an authentication bypass vulnerability where authentication middleware is not properly applied to API endpoints. This results in certain API endpoints being accessible without valid session credentials. This is dangerous for those who have exposed Zerobyte to be used outside of their internal network. A fix has been applied in both version 0.19.0 and 0.18.5. If immediate upgrade is not possible, restrict network access to the Zerobyte instance to trusted networks only using firewall rules or network segmentation. This is only a temporary mitigation; upgrading is strongly recommended.

Affected products

nicotsx zerobyte: before 0.18.5; 0.19.0-beta1 — fixed in 0.18.5

How to fix

Upgrade to a fixed version: nicotsx zerobyte 0.18.5. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2025-68435 or the next vulnerability affects your stack