GHSA-xh69-987w-hrp8

resolv vulnerable to DoS via insufficient DNS domain name length validation

Source: GitHub Advisory Database (reviewed) Moderate CVE-2025-24294

Packages

Ecosystem	Package	Affected	Fixed in
RubyGems	resolv	< 0.2.3	0.2.3
RubyGems	resolv	>= 0.4.0, < 0.6.2	0.6.2
RubyGems	resolv	>= 0.3.0, < 0.3.1	0.3.1

Details

As written in the advisory (Markdown source, shown as plain text).

A denial of service vulnerability has been discovered in the resolv gem bundled with Ruby. ## Details The vulnerability is caused by an insufficient check on the length of a decompressed domain name within a DNS packet. An attacker can craft a malicious DNS packet containing a highly compressed domain name. When the resolv library parses such a packet, the name decompression process consumes a large amount of CPU resources, as the library does not limit the resulting length of the name. This resource consumption can cause the application thread to become unresponsive, resulting in a Denial of Service condition. ## Affected Version The vulnerability affects the resolv gem bundled with the following Ruby series: * Ruby 3.2 series: resolv version 0.2.2 and earlier * Ruby 3.3 series: resolv version 0.3.0 * Ruby 3.4 series: resolv version 0.6.1 and earlier ## Credits Thanks to Manu for discovering this issue. ## History Originally published at 2025-07-08 07:00:00 (UTC)

References

External links from the advisory. They lead to third-party sites.