CVE-2016-20047

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.

CVSS v3 8.4 HIGH

8.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.5 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
http://ekg.chmurka.net/
https://www.exploit-db.com/exploits/40392
https://www.vulncheck.com/advisories/ekg-gadu-local-buffer-overflow-via-username-parameter

Configurations

No configuration.

History

No history.

Information

Published : 2026-03-28 12:16

Updated : 2026-03-30 13:26

NVD link : CVE-2016-20047

Mitre link : CVE-2016-20047

CVE.ORG link : CVE-2016-20047

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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