CVE-2025-68435 is an authentication bypass vulnerability classified under CWE-305 affecting the Zerobyte backup automation tool developed by nicotsx. Versions prior to 0.18.5 and 0.19.0 fail to properly enforce authentication middleware on certain API endpoints, resulting in these endpoints being accessible without valid session credentials. This flaw allows unauthenticated attackers to interact with the Zerobyte API, potentially accessing or manipulating backup data, which can lead to severe confidentiality and integrity breaches. The vulnerability is remotely exploitable over the network without any authentication or user interaction, as indicated by its CVSS vector (AV:N/AC:L/PR:N/UI:N). The vulnerability does not impact availability directly but poses a critical risk due to unauthorized data exposure or modification. The vendor has addressed the issue in versions 0.18.5 and 0.19.0. Until upgrades can be applied, organizations are advised to restrict Zerobyte access to trusted internal networks using firewall rules or network segmentation to mitigate exposure. No public exploits have been reported, but the high CVSS score (9.1) reflects the critical nature of this vulnerability and the urgency for remediation.

For European organizations, the impact of CVE-2025-68435 can be substantial, especially for those relying on Zerobyte for backup automation in environments where the tool is exposed beyond internal networks. Unauthorized access to backup data can lead to data breaches involving sensitive or regulated information, violating GDPR and other data protection laws, potentially resulting in heavy fines and reputational damage. Integrity compromise of backup data can disrupt disaster recovery processes, leading to operational downtime and loss of business continuity. Organizations in sectors such as finance, healthcare, and critical infrastructure are particularly at risk due to the sensitivity of their data and regulatory requirements. The ease of exploitation without authentication increases the threat level, making it feasible for attackers to gain unauthorized access remotely. The lack of known exploits in the wild currently provides a small window for mitigation, but the critical severity demands immediate action to prevent potential attacks.

1. Upgrade Zerobyte instances immediately to version 0.18.5 or 0.19.0 where the authentication bypass vulnerability is fixed. 2. Until upgrades are possible, restrict network access to Zerobyte API endpoints strictly to trusted internal networks using firewall rules, VPNs, or network segmentation to prevent exposure to untrusted or public networks. 3. Conduct thorough audits of Zerobyte deployments to identify any instances exposed externally and remediate accordingly. 4. Implement monitoring and logging on Zerobyte API endpoints to detect any unauthorized access attempts or anomalous activity. 5. Review and enforce least privilege principles for Zerobyte user accounts and API access. 6. Incorporate Zerobyte vulnerability checks into regular vulnerability management and patching cycles. 7. Educate IT and security teams about the critical nature of this vulnerability and the importance of timely patching and network access controls.