High severity · published Jun 10, 2026
CVE-2026-26239
File Station 5
8.1
CVSS
0.4%
EPSS
No
On KEV
Description
A buffer overflow vulnerability has been reported to affect File Station 5. If a remote attacker gains a user account, they can then exploit the vulnerability to modify memory or crash processes.
We have already fixed the vulnerability in the following version:
File Station 5 5.5.6.5208 and later
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 36% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FS
File Station 5 · QNAP Systems Inc.
5.5.0 before 5.5.6.5208 · source: vendor
FS
File Station · Qnap
5.5.6.4691 before 5.5.6.5208 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-26239
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-26239
www.qnap.com
https://www.qnap.com/en/security-advisory/qsa-26-10
More from File Station 5
9.1
CVE-2026-26240
File Station 5
9.1
CVE-2026-26241
File Station 5
8.1
CVE-2026-24724
File Station 5
6.5
CVE-2026-24723
NULL Pointer Dereference in utilRequest.cgi
6.5
CVE-2026-24722
Null Pointer Dereference in File Station 5