CVE-2019-20176

In Pure-FTPd 1.0.49, a stack exhaustion issue was discovered in the listdir function in ls.c.

The product does not properly control the allocation and maintenance of a limited resource.

Name	Vendor	Start Version	End Version
Pure-ftpd	Pureftpd	1.0.49 (including)	1.0.49 (including)
Pure-ftpd	Ubuntu	bionic	*
Pure-ftpd	Ubuntu	disco	*
Pure-ftpd	Ubuntu	eoan	*
Pure-ftpd	Ubuntu	trusty	*
Pure-ftpd	Ubuntu	upstream	*
Pure-ftpd	Ubuntu	xenial	*

Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.

NVD	https://nvd.nist.gov/vuln/detail/CVE-2019-20176
CWE	https://cwe.mitre.org/data/definitions/400.html

Uncontrolled Resource Consumption