QNAP QTS NASFTPD USER Stack-based Buffer Overflow Remote Code Execution Vulnerability
Vulnerability Details
This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of QNAP QTS NASFTPD. Authentication is not required to exploit this vulnerability.
The specific flaw exists within the NASFTPD service, which listens on TCP port 21 by default. When parsing the USER command, the process does not properly validate the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code under the context of root.
Additional Details
QNAP has issued an update to correct this vulnerability. More details can be found at:
https://www.qnap.com/en/security-advisory/nas-201712-15
Disclosure Timeline
- 2017-09-19 - Vulnerability reported to vendor
- 2017-12-20 - Coordinated public release of advisory
Credit
Peter Andersson (@nervoir)
