What’s Vulnerable › Vulnerabilities

CVE-2021-38687: Stack Overflow Vulnerability in Surveillance Station

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-12-29 · updated 2026-06-17
• Weakness: CWE-120

Description

A stack buffer overflow vulnerability has been reported to affect QNAP NAS running Surveillance Station. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of Surveillance Station: QTS 5.0.0 (64 bit): Surveillance Station 5.2.0.4.2 ( 2021/10/26 ) and later QTS 5.0.0 (32 bit): Surveillance Station 5.2.0.3.2 ( 2021/10/26 ) and later QTS 4.3.6 (64 bit): Surveillance Station 5.1.5.4.6 ( 2021/10/26 ) and later QTS 4.3.6 (32 bit): Surveillance Station 5.1.5.3.6 ( 2021/10/26 ) and later QTS 4.3.3: Surveillance Station 5.1.5.3.6 ( 2021/10/26 ) and later

Affected products

• QNAP Systems Inc. Surveillance Station: before 5.2.0.4.2; before 5.2.0.3.2; before 5.1.5.4.6; before 5.1.5.3.6 — fixed in 5.1.5.3.6, 5.1.5.4.6, 5.2.0.3.2, 5.2.0.4.2

How to fix

Upgrade to a fixed version: QNAP Systems Inc. Surveillance Station 5.1.5.3.6, 5.1.5.4.6, 5.2.0.3.2, 5.2.0.4.2. Check the vendor advisory for mitigations.

References

• https://www.qnap.com/en/security-advisory/qsa-21-46
• https://www.qnap.com/en/security-advisory/qsa-21-46

Get alerted when CVE-2021-38687 or the next vulnerability affects your stack