CVE-2026-26239
published 2026-06-10CVE-2026-26239: 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…
PriorityP348high8.1CVSS 3.1
AVNACLPRLUINSUCNIHAH
EPSS
0.29%
21.1th percentile
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
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| qnap | file_station | >= 5.5.6.4691 < 5.5.6.5208 | 5.5.6.5208 |
| qnap_systems_inc | file_station_5 | >= 5.5.0 < 5.5.6.5208 | 5.5.6.5208 |
CVSS provenance
nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
nvdv4.08.7HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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VulDB
QNAP File Station 5 5.5.6.5208 User Account stack-based overflow (qsa-26-37 / EUVD-2026-35979)
vuldb·2026-06-15·CVSS 8.1
CVE-2026-26239 [HIGH] QNAP File Station 5 5.5.6.5208 User Account stack-based overflow (qsa-26-37 / EUVD-2026-35979)
A vulnerability marked as critical has been reported in QNAP File Station 5 5.5.6.5208. Affected by this vulnerability is an unknown functionality of the component User Account Handler. The manipulation leads to stack-based buffer overflow.
This vulnerability is listed as CVE-2026-26239. The attack may be initiated remotely. There is no available exploit.
It is suggested to upgrade the affected component.
GHSA
A buffer overflow vulnerability has been reported to affect File Station 5.
ghsa_unreviewed·2026-06-10
CVE-2026-26239 [HIGH] CWE-121 A buffer overflow vulnerability has been reported to affect File Station 5.
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
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-06-10
Published