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TI-2021-17564 Aliases CVE-2021-40524GHSA-p53v-96v3-p5jg

In Pure-FTPd before 1.0.50, an incorrect max_filesize quota mechanism in the server…

Priority MEDIUM 40CWE-434Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-434.

Summary

In Pure-FTPd before 1.0.50, an incorrect max_filesize quota mechanism in the server allows attackers to upload files of unbounded size, which may lead to denial of service or a server hang. This occurs because a certain greater-than-zero test does not anticipate an initial -1 value. (Versions 1.0.23 through 1.0.49 are affected.)

Why it matters now

EPSS 0.04285 91st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:pureftpd:pure-ftpd:*:*:*:*:*:*:*:*1.0.23 to before 1.0.50VulnerablePureftpd
  • cpe:2.3:a:pureftpd:pure-ftpd:*:*:*:*:*:*:*:* Versions 1.0.23 to before 1.0.50 Vulnerable ·Pureftpd

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-2021-40524
  2. 2026-10-03 Alias added: GHSA-p53v-96v3-p5jg

References

Exploit 1

Patch 2

  • TI-2024-32304 pure-ftpd before 1.0.52 is vulnerable to Buffer Overflow. CVSS 3.1HIGH 8.6
  • TI-2011-01394 The STARTTLS implementation in ftp_parser.c in Pure-FTPd before 1.0.30 does not properly… CVSS 2.0MEDIUM 5.8
  • TI-2017-08960 Downstream version 1.0.46-1 of pure-ftpd as shipped in Fedora was vulnerable to packaging… CVSS 3.0CRITICAL 9.8
  • TI-2020-07487 An issue was discovered in Pure-FTPd 1.0.49. CVSS 3.1HIGH 7.5
  • TI-2020-07415 An issue was discovered in Pure-FTPd 1.0.49. CVSS 3.1HIGH 7.5
  • TI-2020-17954 Pure-FTPd 1.0.48 allows remote attackers to prevent legitimate server use by making… CVSS 3.1HIGH 7.5
See all 10 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences