Unauthorized actions via stack buffer overflow
Published Jun 10, 2026 · Updated Jun 10, 2026
Stack-based buffer overflow in QNAP File Station 5 before 5.5.6.5208 allows remote authenticated users to perform unauthorized actions. QNAP has not published the affected component, input field, buffer operation, or memory-corruption path. A valid user account is required; the vendor reports memory modification or process crashes but does not identify the specific unauthorized actions.
Summary
What happened
Stack-based buffer overflow in QNAP File Station 5 before 5.5.6.5208 allows remote authenticated users to perform unauthorized actions. QNAP has not published the affected component, input field, buffer operation, or memory-corruption path. A valid user account is required; the vendor reports memory modification or process crashes but does not identify the specific unauthorized actions.
The record
- CVE
- CVE-2026-26239
- Published
- Jun 10, 2026
- Updated
- Jun 10, 2026
- Vendor
- Linn Products Limited
- Product
- File Station 5
- Classifications
- CWE-121, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 10, 2026CVE publishedPublication date reported by the CVE source.
- Jun 10, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=5.5.0 <5.5.6.5208
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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