Vulnerability · Published Aug 29, 2025 · Assigned by qnap
CVE-2025-52856VioStor
Critical 9.3
In plain English
A critical-severity improper authentication in VioStor from QNAP Systems Inc.. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities).
Severity (CVSS 4.0)9.3Critical
Exploit odds (30 days)0.7%top 48.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
An improper authentication vulnerability has been reported to affect VioStor. If a remote attacker, they can then exploit the vulnerability to compromise the security of the system. We have already fixed the vulnerability in the following version: VioStor 5.1.6 build 20250621 and later
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| QNAP Systems Inc. | VioStor | 5.1.0 – before 5.1.6 build 20250621 |
Weakness: CWE-287 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N