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vulnerability

Ubuntu: USN-5020-1 (CVE-2021-31810): Ruby vulnerabilities

Severity
5
CVSS
(AV:N/AC:L/Au:N/C:P/I:N/A:N)
Published
Jul 13, 2021
Added
Jul 22, 2021
Modified
Apr 16, 2026

Description

An issue was discovered in Ruby through 2.6.7, 2.7.x through 2.7.3, and 3.x through 3.0.1. A malicious FTP server can use the PASV response to trick Net::FTP into connecting back to a given IP address and port. This potentially makes curl extract information about services that are otherwise private and not disclosed (e.g., the attacker can conduct port scans and service banner extractions).

Solutions

ubuntu-pro-upgrade-libruby2-3ubuntu-pro-upgrade-ruby2-3ubuntu-upgrade-libruby2-5ubuntu-upgrade-libruby2-7ubuntu-upgrade-ruby2-5ubuntu-upgrade-ruby2-7
Title
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