QNAP File Station 5 5.5.6.5243 stack-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k2.37

Summaryinfo

A vulnerability, which was classified as critical, was found in QNAP File Station 5 5.5.6.5243. This vulnerability affects unknown code. Executing a manipulation can lead to stack-based overflow. This vulnerability is registered as CVE-2026-26240. It is possible to launch the attack remotely. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in QNAP File Station 5 5.5.6.5243 and classified as critical. This vulnerability affects some unknown functionality. The manipulation with an unknown input leads to a stack-based overflow vulnerability. The CWE definition for the vulnerability is CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

A buffer overflow vulnerability has been reported to affect File Station 5. The remote attackers can then exploit the vulnerability to modify memory or crash processes. We have already fixed the vulnerability in the following version: File Station 5 5.5.6.5243 and later

The weakness was published by Moritz Abrell as qsa-26-32. The advisory is shared for download at qnap.com. This vulnerability was named CVE-2026-26240 since 02/12/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 5.5.6.5243 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-35983). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: File Station 5 5.5.6.5243

Timelineinfo

02/12/2026 CVE reserved
06/10/2026 +117 days Advisory disclosed
06/10/2026 +0 days VulDB entry created
06/10/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: qnap.com

Advisory: qsa-26-32
Researcher: Moritz Abrell
Status: Confirmed

CVE: CVE-2026-26240 (🔒)
GCVE (CVE): GCVE-0-2026-26240
GCVE (VulDB): GCVE-100-370120
EUVD: 🔒

Entryinfo

Created: 06/10/2026 07:22
Updated: 06/10/2026 10:41
Changes: 06/10/2026 07:22 (68), 06/10/2026 10:41 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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