UBUNTU-CVE-2021-37533 (CVE-2021-37533)

Vulnerability from osv_ubuntu – Published: 2022-12-03 15:15 – Updated: 2025-09-08 16:47 – Source website
VLAI
Details

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
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libcommons-net-java",
            "binary_version": "3.4-2ubuntu2+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "libcommons-net-java",
        "purl": "pkg:deb/ubuntu/libcommons-net-java@3.4-2ubuntu2+esm1?arch=source\u0026distro=esm-apps/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.4-2ubuntu2+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.3-2",
        "3.4-1",
        "3.4-2",
        "3.4-2ubuntu2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libcommons-net-java",
            "binary_version": "3.6-1+deb11u1build0.18.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "libcommons-net-java",
        "purl": "pkg:deb/ubuntu/libcommons-net-java@3.6-1+deb11u1build0.18.04.1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.6-1+deb11u1build0.18.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.6-1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libcommons-net-java",
            "binary_version": "3.6-1+deb11u1build0.20.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "libcommons-net-java",
        "purl": "pkg:deb/ubuntu/libcommons-net-java@3.6-1+deb11u1build0.20.04.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.6-1+deb11u1build0.20.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.6-1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libcommons-net-java",
            "binary_version": "3.6-1+deb11u1build0.22.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "libcommons-net-java",
        "purl": "pkg:deb/ubuntu/libcommons-net-java@3.6-1+deb11u1build0.22.04.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.6-1+deb11u1build0.22.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.6-1"
      ]
    }
  ],
  "aliases": [],
  "details": "Prior to Apache Commons Net 3.9.0, Net\u0027s 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.",
  "id": "UBUNTU-CVE-2021-37533",
  "modified": "2025-09-08T16:47:16Z",
  "published": "2022-12-03T15:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-37533"
    },
    {
      "type": "REPORT",
      "url": "https://lists.apache.org/thread/o6yn9r9x6s94v97264hmgol1sf48mvx7"
    },
    {
      "type": "REPORT",
      "url": "https://issues.apache.org/jira/browse/NET-711"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/apache/commons-net/commit/b0bff89f70cfea70009e22f87639816cc3993974"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-37533"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-6037-1"
    }
  ],
  "related": [
    "USN-6037-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-37533"
  ]
}



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