Vulnerability · Published Dec 3, 2022 · Assigned by apache

CVE-2021-37533Apache Commons Net's FTP client trusts the host from PASV response by default

Medium 6.5

In plain English

A medium-severity improper input validation in Apache Commons Net from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 2.1% (higher than 82% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)2.1%top 18.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12libcommons-net-java3.9.0-1DEBIAN-CVE-2021-37533
Debian:13libcommons-net-java3.9.0-1DEBIAN-CVE-2021-37533
Debian:14libcommons-net-java3.9.0-1DEBIAN-CVE-2021-37533
Mavencommons-net:commons-net3.9.0GHSA-cgp8-4m63-fhh5
Ubuntu:22.04:LTSlibcommons-net-java3.6-1+deb11u1build0.22.04.1USN-6037-1
Ubuntu:22.04:LTSlibcommons-net-java3.6-1+deb11u1build0.22.04.1UBUNTU-CVE-2021-37533

Affected products (as reported)

VendorProductVersions
Apache Software Foundation Apache Commons Net Apache Commons Net – before 3.9.0

Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

References