Path traversal in the qsyncsrv.cgi component allows a remote attacker who has authenticated to read unintended files from the host. This flaw can expose configuration files, logs, or other system data that should be protected, creating a confidentiality breach. The vulnerability is limited to authentication impersonation and does not grant code execution or wider system control.

Qsync Central for QNAP Systems Inc. is vulnerable in any release prior to Qsync Central 5.0.0.7, Qsync Central 5.1.0.3, Qsync Central 5.2.0.5, or Qsync Central 5.3.0.2. All earlier patches in the Qsync Central product line are affected until the mentioned version thresholds are applied.

The CVSS score of 5.3 indicates medium severity, and the EPSS score of less than 1% suggests that exploitation is unlikely at present. The issue is not listed in the CISA KEV catalog, reducing immediate threat pressure. Exploitation requires an account that can access the Qsync service, and the attacker must leverage the qsyncsrv.cgi endpoint. Once authenticated, the attacker can request illegal paths and retrieve data from outside the intended directory.