CVE-2020-36964: YATinyWinFTP Denial of Service via Out-of-Bounds Write
CVE-2020-36964 affects the YATinyWinFTP FTP server and allows a remote attacker to crash the FTP service through a malformed command. The record rates it 9.8 under CVSS 3.1 and 8.7 under CVSS 4.0, and classifies it as an out-of-bounds write (CWE-787). No affected or fixed versions are listed, and it is not in the CISA KEV catalog.
Overview
CVE-2020-36964 is a denial of service issue in the YATinyWinFTP FTP server. According to the record, a malformed command sent to the service can trigger a buffer overflow and crash the FTP service. The CNA, disclosure@vulncheck.com, classifies the weakness as an out-of-bounds write (CWE-787).
Impact
- Loss of availability of the FTP service, which can interrupt any file transfer workflow that depends on it.
- The CNA provides a CVSS 3.1 base score of 9.8 with the vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, which reflects network reachability and no required privileges.
- The same CNA provides a CVSS 4.0 score of 8.7.
- The record describes a crash, so the stated effect is service disruption. It does not describe code execution, and no source in the record confirms that outcome.
Affected products and versions
The record does not list affected products or versions. Check the project repository and the vendor references for version details before concluding which builds are impacted.
Exploitation status
The CISA KEV catalog does not list this CVE in the record, so no active exploitation is claimed here. No confirmed exploitation appears in the sources consulted. The record links to a public Exploit-DB entry, but the presence of a public entry does not confirm exploitation in the wild.
Remediation and mitigation
- The record does not list a fixed version. The absence of a fixed version does not mean that no fix exists, so check the project repository and the advisory for updates.
- Restrict access to the FTP service to trusted networks and remove it from internet exposure where it is not needed.
- Disable or uninstall FTP services that are not in active use.
- Place the service behind network controls that limit which hosts can reach it.
Detection guidance
- Monitor for unexpected restarts or crashes of the FTP service and correlate them with inbound connections.
- Review FTP logs for connections that send unusual or malformed commands from unexpected sources.
- Alert on repeated service failures, which can indicate that the service is being targeted.
Limitations of the available information
- The record contains no affected product versions and no fixed versions.
- No EPSS score or SSVC data is present in the record, so exploitation likelihood cannot be assessed from it.
- The record shows the NVD source status as Deferred, so the NVD analysis may be incomplete.
- The record does not describe the exact trigger conditions beyond its summary, and this analysis does not provide them.
Frequently asked questions
Does CVE-2020-36964 allow code execution?
The record describes a denial of service caused by a crash of the FTP service. It does not describe code execution, and no source in the record confirms it.
Is CVE-2020-36964 known to be actively exploited?
The CVE is not listed in the CISA KEV catalog in the record, and no confirmed active exploitation appears in the sources consulted. The record links to a public Exploit-DB entry, which does not by itself confirm exploitation.
Which version should I upgrade to?
The record lists no fixed version. Check the project repository and the advisory for update information, since the absence of a fixed version in the record does not mean no fix exists.
This analysis was drafted with AI assistance from verified source data and automatically checked against it.