CVE-2021-37533

Apache Commons Net's FTP client trusts the host from PASV response by default

Description

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.18%
Vendor Advisory debian.org Vendor Advisory apache.org
Affected: Apache Software Foundation Apache Commons Net
Published at:
Updated at:

References

Link Tags
https://lists.apache.org/thread/o6yn9r9x6s94v97264hmgol1sf48mvx7 vendor advisory mailing list issue tracking
http://www.openwall.com/lists/oss-security/2022/12/03/1 mailing list third party advisory issue tracking
https://lists.debian.org/debian-lts-announce/2022/12/msg00038.html third party advisory mailing list
https://www.debian.org/security/2022/dsa-5307 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-37533?
CVE-2021-37533 has been scored as a medium severity vulnerability.
How to fix CVE-2021-37533?
To fix CVE-2021-37533, 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-2021-37533 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-37533 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-37533?
CVE-2021-37533 affects Apache Software Foundation Apache Commons Net.
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