Bug 2431679 (CVE-2021-47865)

Summary: CVE-2021-47865 proftpd: ProFTPD: Denial of Service via multiple simultaneous FTP connections
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in ProFTPD. A remote attacker can exploit this denial of service (DoS) vulnerability by creating multiple simultaneous File Transfer Protocol (FTP) connections. This action can exhaust the server's connection limits, preventing legitimate users from accessing the service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-01-21 18:01:38 UTC
ProFTPD 1.3.7a contains a denial of service vulnerability that allows attackers to overwhelm the server by creating multiple simultaneous FTP connections. Attackers can repeatedly establish connections using threading to exhaust server connection limits and block legitimate user access.