CVE-2021-28797: Stack Buffer Overflow in Surveillance Station

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 5.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-14 · updated 2026-06-17
Weakness: CWE-121

Description

A stack-based buffer overflow vulnerability has been reported to affect QNAP NAS devices running Surveillance Station. If exploited, this vulnerability allows attackers to execute arbitrary code. QNAP have already fixed this vulnerability in the following versions: Surveillance Station 5.1.5.4.3 (and later) for ARM CPU NAS (64bit OS) and x86 CPU NAS (64bit OS) Surveillance Station 5.1.5.3.3 (and later) for ARM CPU NAS (32bit OS) and x86 CPU NAS (32bit OS)

Affected products

QNAP Systems Inc. Surveillance Station: before 5.1.5.3.3; from 5.1.5.4.0 before 5.1.5.4.3 — fixed in 5.1.5.3.3, 5.1.5.4.3

How to fix

Upgrade to a fixed version: QNAP Systems Inc. Surveillance Station 5.1.5.3.3, 5.1.5.4.3. Check the vendor advisory for mitigations.

References

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