CVE-2021-40524

Public Exploit

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.)

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.57%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/jedisct1/pure-ftpd/pull/158 third party advisory exploit
https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50 third party advisory patch
https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-40524?
CVE-2021-40524 has been scored as a high severity vulnerability.
How to fix CVE-2021-40524?
To fix CVE-2021-40524, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-40524 being actively exploited in the wild?
It is possible that CVE-2021-40524 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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