CVE-2021-40524

7.5 HIGH
Published: September 05, 2021 Modified: November 04, 2025

Description

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.)

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50
Source: cve@mitre.org
Patch Third Party Advisory
https://github.com/jedisct1/pure-ftpd/pull/158
Source: cve@mitre.org
Exploit Third Party Advisory
https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://github.com/jedisct1/pure-ftpd/pull/158
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory

7 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.5 / 10.0
EPSS (Exploit Probability)
24.0%
96th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

pureftpd