CVE-2021-31810

Ruby vulnerability

CVSS

5.8

EPSS

3.0%

EPSS pct

86th

Exploited

No known

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).

Affected vendor

Ruby Lang

Affected product

Ruby

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

Published

2021-07-13

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring no privileges, no user interaction. Successful exploitation leads to low impact to confidentiality.

Its EPSS score of 3.0% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 86% of all scored CVEs.

Check your external exposure to CVE-2021-31810

Confirm whether Ruby Lang Ruby is running on any internet-facing host or subdomain.
Match discovered service fingerprints against the version affected by CVE-2021-31810.
Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2021-31810

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