Local code execution via oversized username copy
Published Mar 28, 2026 · Updated Mar 28, 2026
Buffer overflow in EKG 1:1.9~pre+r2855-3+b1 allows local users to execute arbitrary code via an oversized username argument. The ioctld_socket path passes the crafted value to strlcpy, overflowing the username buffer after 258 bytes and overwriting the instruction pointer. The attacker needs local access to invoke the console client with the argument, and resulting shellcode runs only with the affected user's privileges.
Summary
What happened
Buffer overflow in EKG 1:1.9~pre+r2855-3+b1 allows local users to execute arbitrary code via an oversized username argument. The ioctld_socket path passes the crafted value to strlcpy, overflowing the username buffer after 258 bytes and overwriting the instruction pointer. The attacker needs local access to invoke the console client with the argument, and resulting shellcode runs only with the affected user's privileges.
The record
- CVE
- CVE-2016-20047
- Published
- Mar 28, 2026
- Updated
- Mar 28, 2026
- Vendor
- EKG
- Product
- EKG
- Classifications
- CWE-787, T1203
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 28, 2026CVE publishedPublication date reported by the CVE source.
- Mar 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1:1.9~pre+r2855-3+b1
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- EKG Gadu 1.9 Local Buffer Overflowfunctional · demonstrated
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Technologies
Your stack
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Your stack
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