CVE-2026-26239: qnap systems inc. file station 5 Stack-based Buffer Overflow
CVSS: 8.1v3.1HighModified
Published 10-06-2026Last modified 17-06-2026
Vulnerability summary
CVE-2026-26239 is a high (CVSS 8.1) Stack-based Buffer Overflow vulnerability in qnap systems inc. file station 5. EPSS estimates a 0.52% chance of exploitation in the next 30 days, higher than 42.9% of scored vulnerabilities.
CVSS score
8.1/10
010
High · v3.1 (NVD)EPSS score
0.52%
0%100%
Low · +0.09 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 10-06-2026PublishedVulnerability first disclosed.
- 17-06-2026Last modifiedVulnerability information updated.
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 metrics
3 scores · 2 sources · 2 versionsMedium 6.3Preferred score · CVE.org (CNA)
CVSS: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:USourcesAll 2 agree
- NVDNIST6.3MediumCVSS: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:U/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
High 8.1Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:HSourcesSingle source
EPSS trend
Probability
0.52%
Chance of exploitation in the next 30 days
Percentile
43%
Versus all other CVEs
30-day change
+0.09 pp
From 0.42% on 21-09-2026
21-09-202621-10-2026
EPSS score0.52%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Qnap1 product
- file_station≥ 5.5.6.4691, < 5.5.6.5208
Qnap systems inc.1 product
- file station 5≥ 5.5.0, < 5.5.6.5208
2 vendors · 2 products