ZDI-21-783: QNAP NAS Hybrid Backup Missing Authentication for Critical Function Remote Code Execution Vulnerability
This vulnerability allows remote attackers to execute arbitrary code on affected installations of QNAP NAS. Authentication is not required to exploit this vulnerability. The specific flaw exists within the RTSS server, which listens on TCP port 8899 by default. The issue results from the lack of authentication prior to allowing alterations to the system configuration. An attacker can leverage this vulnerability to execute arbitrary code in the context of the Administrator.
| Affected Software | Affected Version | How to fix |
|---|---|---|
| QNAP NAS |
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Reference Links
Frequently Asked Questions
What is the severity of ZDI-21-783?
The severity of ZDI-21-783 is high due to the potential for remote code execution without authentication.
How do I fix ZDI-21-783?
To fix ZDI-21-783, it is recommended to update the QNAP NAS firmware to the latest version provided by the vendor.
What systems are affected by ZDI-21-783?
ZDI-21-783 affects QNAP NAS devices with the RTSS server running on TCP port 8899.
Can ZDI-21-783 be exploited remotely?
Yes, ZDI-21-783 can be exploited remotely without the need for authentication.
What is the risk of not addressing ZDI-21-783?
Not addressing ZDI-21-783 may allow attackers to execute arbitrary code on the affected QNAP NAS devices.
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