CVE-2021-40524

EUVD-2021-27700
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.)
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 95%
Affected Products (NVD)
VendorProductVersion
pureftpdpure-ftpd
1.0.23 ≤
𝑥
< 1.0.50
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
pure-ftpd
bookworm
1.0.50-2.1
fixed
bullseye
no-dsa
buster
no-dsa
sid
1.0.50-2.2
fixed
stretch
no-dsa
trixie
1.0.50-2.2
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
pure-ftpd
bionic
needs-triage
focal
needs-triage
hirsute
ignored
impish
ignored
jammy
needs-triage
kinetic
ignored
lunar
ignored
mantic
ignored
noble
needs-triage
trusty
dne
xenial
needs-triage
Common Weakness Enumeration
References
https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4
https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50
https://github.com/jedisct1/pure-ftpd/pull/158
https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4
https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50
https://github.com/jedisct1/pure-ftpd/pull/158
https://lists.debian.org/debian-lts-announce/2025/11/msg00003.html