7.5
HIGH
CVE-2021-40524
Pure-FTPd UnboundedFileSize Vulnerability
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.)

INFO

Published Date :

Sept. 5, 2021, 7:15 p.m.

Last Modified :

Nov. 21, 2024, 6:24 a.m.

Remotely Exploitable :

Yes !

Impact Score :

3.6

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2021-40524 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Pureftpd pure-ftpd
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-40524.

URL Resource
https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4 Patch Third Party Advisory
https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50 Patch Third Party Advisory
https://github.com/jedisct1/pure-ftpd/pull/158 Exploit Third Party Advisory
https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4 Patch Third Party Advisory
https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50 Patch Third Party Advisory
https://github.com/jedisct1/pure-ftpd/pull/158 Exploit Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-40524 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-40524 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4
    Added Reference https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50
    Added Reference https://github.com/jedisct1/pure-ftpd/pull/158
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Modified Analysis by [email protected]

    Nov. 26, 2021

    Action Type Old Value New Value
    Changed Reference Type https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4 No Types Assigned https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4 Patch, Third Party Advisory
    Changed Reference Type https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50 No Types Assigned https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50 Patch, Third Party Advisory
    Changed CPE Configuration OR *cpe:2.3:a:pureftpd:pure-ftpd:1.0.49:*:*:*:*:*:*:* OR *cpe:2.3:a:pureftpd:pure-ftpd:*:*:*:*:*:*:*:* versions from (including) 1.0.23 up to (excluding) 1.0.50
  • CVE Modified by [email protected]

    Nov. 24, 2021

    Action Type Old Value New Value
    Changed Description In Pure-FTPd 1.0.49, 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. 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.)
    Added Reference https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4 [No Types Assigned]
    Added Reference https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50 [No Types Assigned]
  • Initial Analysis by [email protected]

    Sep. 10, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:N/I:N/A:P)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Changed Reference Type https://github.com/jedisct1/pure-ftpd/pull/158 No Types Assigned https://github.com/jedisct1/pure-ftpd/pull/158 Exploit, Third Party Advisory
    Added CWE NIST CWE-434
    Added CPE Configuration OR *cpe:2.3:a:pureftpd:pure-ftpd:1.0.49:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-40524 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-40524 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.23 }} -0.04%

score

0.60384

percentile

CVSS31 - Vulnerability Scoring System
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