VDB-214779 · CVE-2021-37533 · GCVE-0-2021-37533

Apache Commons Net up to 3.8.x PASV Response input validation

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5.6	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Apache Commons Net up to 3.8.x. It has been classified as problematic. This issue affects some unknown processing of the component PASV Response Handler. Performing a manipulation results in input validation. This vulnerability is cataloged as CVE-2021-37533. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Apache Commons Net up to 3.8.x. This affects an unknown code block of the component PASV Response Handler. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was shared 12/03/2022. It is possible to read the advisory at lists.apache.org. This vulnerability is uniquely identified as CVE-2021-37533 since 07/26/2021. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 3.9.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Apache

Name

Commons Net

Version

License

open-source

Website

Vendor: https://www.apache.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.6

VulDB Base Score: 5.0
VulDB Temp Score: 4.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Commons Net 3.9.0

Timelineinfo

07/26/2021 🔍
12/03/2022 +495 days 🔍
12/03/2022 +0 days 🔍
04/25/2025 +874 days 🔍

Sourcesinfo

Vendor: apache.org

Advisory: lists.apache.org
Status: Confirmed

CVE: CVE-2021-37533 (🔍)
GCVE (CVE): GCVE-0-2021-37533
GCVE (VulDB): GCVE-100-214779

Entryinfo

Created: 12/03/2022 19:01
Updated: 04/25/2025 04:26
Changes: 12/03/2022 19:01 (39), 12/26/2022 08:42 (11), 04/25/2025 04:26 (16)
Complete: 🔍
Cache ID: 216:2FF:103