CVE-2021-37533 (GCVE-0-2021-37533)

Vulnerability from cvelistv5 – Published: 2022-12-03 00:00 – Updated: 2025-04-24 15:25
VLAI
Title
Apache Commons Net's FTP client trusts the host from PASV response by default
Summary
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.
Severity
No CVSS data available.
CWE
  • CWE-20 - Improper Input Validation
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache Commons Net Affected: Apache Commons Net , < 3.9.0 (custom)
Create a notification for this product.
Credits
Apache Commons would like to thank ZeddYu Lu for reporting this issue.
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.