{"id":"CVE-2016-20047","aliases":["EUVD-2016-10849","GHSA-v8g9-6wqg-f384"],"status":"published","title":"EKG Gadu 1.9 Local Buffer Overflow via Username Parameter","description":"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.","severity":{"version":"4.0","score":8.6,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-07","score":0.00152,"percentile":0.04416,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-787"],"published":"2026-03-28T11:58:07Z","modified":"2026-06-17T00:43:09Z","products":[{"vendor":"ekg","product":"ekg gadu"}],"references":[{"url":"https://www.exploit-db.com/exploits/40392","tags":["exploit"]},{"url":"http://ekg.chmurka.net/","tags":["product"]},{"url":"https://www.vulncheck.com/advisories/ekg-gadu-local-buffer-overflow-via-username-parameter","tags":["third-party-advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2016-20047"},{"url":"http://ekg.chmurka.net"},{"url":"https://github.com/advisories/GHSA-v8g9-6wqg-f384"}],"sources":{"cve":[{"id":"CVE-2016-20047","title":"EKG Gadu 1.9 Local Buffer Overflow via Username Parameter","description":"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.","status":"published","published":"2026-03-28T11:58:07.645Z","modified":"2026-03-30T17:30:50.428Z","cvss":[{"version":"4.0","score":8.6,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":8.4,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T14:33:30.359814Z"}],"euvd":[{"id":"EUVD-2016-10849","description":"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.","status":"published","published":"2026-03-28T11:58:07Z","modified":"2026-03-30T17:30:50Z","cvss":[{"version":"4.0","score":8.6,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T19:25:25.878486Z"}],"ghsa":[{"id":"GHSA-v8g9-6wqg-f384","title":"EKG Gadu 1.9~pre+r2855-3+b1 contains a local buffer overflow vulnerability in the username...","description":"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.","status":"published","published":"2026-03-28T12:30:29Z","modified":"2026-03-28T12:30:35Z","cvss":[{"version":"4.0","score":8.6,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":8.4,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T15:06:54.610516Z"}],"nvd":[{"id":"CVE-2016-20047","description":"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.","status":"published","published":"2026-03-28T12:16:01.013Z","modified":"2026-06-17T00:43:09.433Z","cvss":[{"version":"4.0","score":8.6,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":8.4,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T14:03:40.811555Z"}]}}