CVE-2022-38802 is a medium-severity vulnerability affecting Zkteco BioTime versions prior to 8.5.3 Build:20200816.447. This vulnerability arises from incorrect access control combined with a cross-site scripting (XSS) flaw (CWE-79) in the PDF export functionality. Specifically, an authenticated administrator user can exploit XSS vectors injected into various modules such as resign, private message, manual log, time interval, attshift, and holiday. By injecting malicious scripts into these modules, the attacker can trigger the PDF generator to execute the payload when exporting data as a PDF document. This results in the ability to read local files on the server, thereby compromising confidentiality. The vulnerability requires administrator-level privileges and user interaction (exporting data as PDF) to be exploited. The CVSS v3.1 score is 6.2, reflecting a medium impact primarily on confidentiality with no impact on integrity or availability. The attack vector is network-based with low attack complexity, but the prerequisite of high privileges and user interaction limits the scope of exploitation. No public exploits are currently known in the wild, and no patches have been explicitly linked, although upgrading to version 8.5.3 or later is implied to remediate the issue. The vulnerability is notable because it leverages XSS in a non-traditional manner to escalate access to local file reading, which is atypical for standard XSS attacks. This could lead to leakage of sensitive biometric or attendance data stored locally by the BioTime system.

For European organizations using Zkteco BioTime for workforce management and biometric attendance tracking, this vulnerability poses a risk to the confidentiality of sensitive employee data. Unauthorized local file reading could expose personal biometric information, attendance logs, or configuration files containing sensitive operational details. Given that exploitation requires administrator credentials, the threat is heightened if internal accounts are compromised or if insider threats exist. The ability to read local files without integrity or availability impact means attackers could silently exfiltrate data without disrupting operations, complicating detection. This could lead to privacy violations under GDPR, reputational damage, and potential regulatory penalties. Organizations in sectors with strict data protection requirements, such as healthcare, finance, and government, are particularly at risk. Additionally, the vulnerability could be leveraged as a foothold for further lateral movement or privilege escalation within the network if combined with other vulnerabilities or misconfigurations.

1. Upgrade Zkteco BioTime to version 8.5.3 Build:20200816.447 or later, where this vulnerability is addressed. 2. Restrict administrator access strictly to trusted personnel and enforce strong authentication mechanisms, including multi-factor authentication, to reduce risk of credential compromise. 3. Monitor and audit administrator activities, especially actions involving PDF exports and modifications to modules like resign, private message, manual log, time interval, attshift, and holiday. 4. Implement network segmentation to isolate the BioTime server from broader enterprise networks, limiting exposure if compromised. 5. Employ web application firewalls (WAFs) with custom rules to detect and block suspicious script injections targeting the PDF export functionality. 6. Conduct regular security assessments and penetration tests focusing on access control and input validation in the BioTime system. 7. Educate administrators about the risks of XSS and the importance of validating inputs before exporting data. 8. If patching is delayed, consider disabling PDF export features temporarily or restricting export capabilities to reduce attack surface.