Summaryinfo

A vulnerability classified as critical has been found in EKG Gadu 11.9~pre+r2855-3+b1. Affected by this vulnerability is the function strlcpy. The manipulation leads to out-of-bounds write. This vulnerability is documented as CVE-2016-20047. The attack needs to be performed locally. Additionally, an exploit exists.

Detailsinfo

A vulnerability was found in EKG Gadu 11.9~pre+r2855-3+b1 and classified as critical. This issue affects the function strlcpy. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

EKG Gadu 1.9~pre+r2855-3+b1 contains a local buffer overflow vulnerability in the username handling that allows local attackers to execute arbitrary code by supplying an oversized username string. Attackers can trigger the overflow in the strlcpy function by passing a crafted buffer exceeding 258 bytes to overwrite the instruction pointer and execute shellcode with user privileges.

The advisory is shared at exploit-db.com. The identification of this vulnerability is CVE-2016-20047 since 03/28/2026. The exploitation is known to be easy. An attack has to be approached locally. Technical details as well as a public exploit are known.

The exploit is available 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 (40392) and EUVD (EUVD-2016-10849). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

• EKG

Name

• Gadu

Version

• 11.9~pre+r2855-3+b1

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

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