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Case File

CVE-2021-28809

CRITICAL · CVSS 9.8 EPSS 15.80% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-07-08 · Last synced 2026-08-04

CyberRota Analysis

This is a critical severity vulnerability with a CVSS score of 9.8. Public exploit code or proof-of-concept references have been detected in its references. Its EPSS score suggests a 15.8% probability of exploitation in the next 30 days.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
exploit

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-28809
Severity
CRITICAL
CVSS
9.8
EPSS
15.80%

Original NVD Description

An improper access control vulnerability has been reported to affect certain legacy versions of HBS 3. If exploited, this vulnerability allows attackers to compromise the security of the operating system.QNAP have already fixed this vulnerability in the following versions of HBS 3: QTS 4.3.6: HBS 3 v3.0.210507 and later QTS 4.3.4: HBS 3 v3.0.210506 and later QTS 4.3.3: HBS 3 v3.0.210506 and later

Related CVEs

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