Improper input validation in Apache Commons Net

CVE-2021-37533

Prior to Apache Commons Net 3.9.0, Net's FTP client trusts the host from PASV response by default. A malicious server can redirect the Commons Net code to use a different host, but the user has to connect to the malicious server in the first place. This may lead to leakage of information about services running on the private network of the client. The default in version 3.9.0 is now false to ignore such hosts, as cURL does. See https://issues.apache.org/jira/browse/NET-711.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.019 (77.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-37533?
CVE-2021-37533 is a medium-severity vulnerability in Apache Commons Net, classified under Improper Input Validation. CVSS score: 6.5/10. Published 2022-12-03.
How severe is CVE-2021-37533?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2021-37533 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.