CVE-2026-26239: CWE-121 in QNAP Systems Inc. File Station 5
CVE-2026-26239 is a high-severity buffer overflow vulnerability in QNAP Systems Inc. File Station 5. A remote attacker with a user account can exploit this flaw to modify memory or crash processes. The issue is fixed in File Station 5 version 5. 5. 6. 5208 and later.
AI Analysis
Technical Summary
This vulnerability (CWE-121) in File Station 5 allows a remote attacker who has obtained a user account to trigger a buffer overflow, potentially leading to memory modification or process crashes. The vulnerability affects version 5.5.0 and is resolved in version 5.5.6.5208 and later. The CVSS 4.0 base score is 8.7, indicating high severity with network attack vector, low attack complexity, no user interaction, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation can result in unauthorized memory modification or denial of service via process crashes. This can compromise system stability and potentially lead to further exploitation depending on the memory corruption consequences.
Mitigation Recommendations
Upgrade File Station 5 to version 5.5.6.5208 or later where this vulnerability is fixed. No other mitigation or temporary workaround is indicated.
CVE-2026-26239: CWE-121 in QNAP Systems Inc. File Station 5
Description
CVE-2026-26239 is a high-severity buffer overflow vulnerability in QNAP Systems Inc. File Station 5. A remote attacker with a user account can exploit this flaw to modify memory or crash processes. The issue is fixed in File Station 5 version 5. 5. 6. 5208 and later.
CVSS v4.0
Score 8.7high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-121) in File Station 5 allows a remote attacker who has obtained a user account to trigger a buffer overflow, potentially leading to memory modification or process crashes. The vulnerability affects version 5.5.0 and is resolved in version 5.5.6.5208 and later. The CVSS 4.0 base score is 8.7, indicating high severity with network attack vector, low attack complexity, no user interaction, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation can result in unauthorized memory modification or denial of service via process crashes. This can compromise system stability and potentially lead to further exploitation depending on the memory corruption consequences.
Mitigation Recommendations
Upgrade File Station 5 to version 5.5.6.5208 or later where this vulnerability is fixed. No other mitigation or temporary workaround is indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- qnap
- Date Reserved
- 2026-02-12T02:21:35.483Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a28dcc68dd33fbd85dbad78
Added to database: 6/10/2026, 3:40:54 AM
Last enriched: 6/10/2026, 3:55:35 AM
Last updated: 6/10/2026, 5:18:30 AM
Views: 6
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