Local code execution via oversized connection name
Published Mar 28, 2026 · Updated Mar 28, 2026
Out-of-bounds write in CERN zFTP 20061220+dfsg3-4.1 allows local users to crash the client or execute code via an oversized connection name. The connection setup path copies the attacker-controlled NAME value through __strcpy_chk into an 80-byte destination, allowing excess data to overwrite control data. The attacker must be able to invoke the Linux client locally; successful code execution remains in the invoking user's privilege context.
Summary
What happened
Out-of-bounds write in CERN zFTP 20061220+dfsg3-4.1 allows local users to crash the client or execute code via an oversized connection name. The connection setup path copies the attacker-controlled NAME value through __strcpy_chk into an 80-byte destination, allowing excess data to overwrite control data. The attacker must be able to invoke the Linux client locally; successful code execution remains in the invoking user's privilege context.
The record
- CVE
- CVE-2016-20046
- Published
- Mar 28, 2026
- Updated
- Mar 28, 2026
- Vendor
- CERN
- Product
- zFTP
- 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
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=20061220+dfsg3-4.1
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
- zFTP Client 20061220 Connection Name Local Buffer Overflowproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo