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TI-2021-22479 Aliases CVE-2021-47865GHSA-mf77-27mv-mhm4

ProFTPD 1.3.7a - Remote Denial of Service

Priority HIGH 77CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-770.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00597 48th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ProFTPDProFTPD1.3.7a—No fix listedCNA
  • ProFTPD VendorProFTPD Affected 1.3.7a Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:proftpd:proftpd:*:*:*:*:*:*:*:*——ProFTPD
  • cpe:2.3:a:proftpd:proftpd:*:*:*:*:*:*:*:* Versions — — ·ProFTPD

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-47865
  2. 2026-10-03 Alias added: GHSA-mf77-27mv-mhm4

References

  • TI-2015-02923 Access control flaw in ProFTPD mod_copy allows arbitrary file access KEVCVSS 3.1CRITICAL 10.0
  • TI-2010-03974 Multiple stack-based buffer overflows in the pr_netio_telnet_gets function in netio.c in… CVSS 2.0HIGH 10.0
  • TI-2010-05061 ProFTPD 1.3.3c Backdoor Command Execution CVSS 4.0CRITICAL 9.3
  • TI-2019-09597 An arbitrary file copy vulnerability in mod_copy in ProFTPD up to 1.3.5b allows for… CVSS 3.1CRITICAL 9.8
  • TI-2026-30493 SQL injection in ProFTPD CVSS 3.1HIGH 8.1
  • TI-2023-26623 The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6… CVSS 3.1MEDIUM 5.9
See all 34 →

Sources