Summaryinfo

A vulnerability identified as critical has been detected in zFTP Client 20061220+dfsg3-4.1. The impacted element is the function strcpy_chk. This manipulation of the argument Name causes out-of-bounds write. This vulnerability is tracked as CVE-2016-20046. The attack is restricted to local execution. Moreover, an exploit is present.

Detailsinfo

A vulnerability classified as critical was found in zFTP Client 20061220+dfsg3-4.1. Affected by this vulnerability is the function strcpy_chk. The manipulation of the argument NAME with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

zFTP Client 20061220+dfsg3-4.1 contains a buffer overflow vulnerability in the NAME parameter handling of FTP connections that allows local attackers to crash the application or execute arbitrary code. Attackers can supply an oversized NAME value exceeding the 80-byte buffer allocated in strcpy_chk to overwrite the instruction pointer and execute shellcode with user privileges.

The advisory is shared at exploit-db.com. This vulnerability is known as CVE-2016-20046 since 03/28/2026. The exploitation appears to be easy. An attack has to be approached locally. Technical details and also a public exploit are known.

It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Exploit-DB (40203) and EUVD (EUVD-2016-10847). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• zFTP

Name

• Client

Version

• 20061220+dfsg3-4.1

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

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