CVE-2021-28809

Missing Authentication for Critical Function in RTRR Server in HBS3

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

Remediation

Solution:

  • 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

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.58%
Vendor Advisory qnap.com
Affected: QNAP Systems Inc. HBS 3
Affected: QNAP Systems Inc. HBS 3
Affected: QNAP Systems Inc. HBS 3
Published at:
Updated at:

References

Link Tags
https://www.qnap.com/en/security-advisory/qsa-21-19 vendor advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-783/ vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-28809?
CVE-2021-28809 has been scored as a critical severity vulnerability.
How to fix CVE-2021-28809?
To fix CVE-2021-28809: 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
Is CVE-2021-28809 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-28809 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-28809?
CVE-2021-28809 affects QNAP Systems Inc. HBS 3, QNAP Systems Inc. HBS 3, QNAP Systems Inc. HBS 3.
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