CVE-2021-4189 Details
A flaw was found in Python, specifically in the FTP (File Transfer Protocol) client library in PASV (passive) mode. The issue is how the FTP client trusts the host from the PASV response by default. This flaw allows an attacker to set up a malicious FTP server that can trick FTP clients into connecting back to a given IP address and port. This vulnerability could lead to FTP client scanning ports, which otherwise would not have been possible.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2021-4189
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.3 Probability of exploitation activity being observed over the next 30 days (53rd percentile)
CVSS score for CVE-2021-4189
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
5.3 Medium
Products affected by CVE-2021-4189
Python 3.7.5
Python 3.7.6
Python 3.7.7
Python 3.7.8
Python 3.7.9
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Low
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CVE-2021-4189 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 11,895 32.55%
CN 6,780 18.55%
DE 2,403 6.58%
FR 1,279 3.50%
SG 1,163 3.18%
HK 1,035 2.83%
JP 877 2.40%
KR 849 2.32%
GB 770 2.11%
ES 710 1.94%

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CVE-2021-4189 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Technology 21,316 84.53%
Telecommunications 3,286 13.03%
Education 368 1.46%
Retail 79 0.31%
Government/Politics 35 0.14%
Media/Entertainment 29 0.12%
Business Services 27 0.11%
Finance 16 0.06%
Manufacturing 12 0.05%
Utilities 10 0.04%

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