CVE-2021-31810

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).

How to fix CVE-2021-31810

To remediate CVE-2021-31810, upgrade the affected package to a fixed version below.

—upgrade to 2.6.8-r0 or later
—upgrade to 2.6.8 or later
—upgrade to 2.6.8 or later
—upgrade to 9.3.9.0+ds-1 or later
—upgrade to 2.7.4-1 or later

Is CVE-2021-31810 being exploited?

Low — EPSS is 0.7%, meaning exploitation activity has not been observed at scale.

Affected packages (5)

from 0, < 2.6.8-r0
from 0, < 2.6.8, >= 2.7.0, < 2.7.4, >= 3.0.0, < 3.0.2
from 0, < 2.6.8, >= 2.7.0, < 2.7.4, >= 3.0.0, < 3.0.2
from 0, < 9.3.9.0+ds-1
from 0, < 2.7.4-1

CVSS scores

Source	Version	Severity	Vector
osv	CVSS 3.1	MEDIUM5.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N