Описание
resolv vulnerable to DoS via insufficient DNS domain name length validation
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)
Пакеты
resolv
< 0.2.3
0.2.3
resolv
>= 0.4.0, < 0.6.2
0.6.2
resolv
>= 0.3.0, < 0.3.1
0.3.1
EPSS
6.6 Medium
CVSS4
5.3 Medium
CVSS3
CVE ID
Дефекты
Связанные уязвимости
The attack vector is a potential Denial of Service (DoS). 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.
The attack vector is a potential Denial of Service (DoS). 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.
The attack vector is a potential Denial of Service (DoS). 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.
The attack vector is a potential Denial of Service (DoS). The vulnerab ...
EPSS
6.6 Medium
CVSS4
5.3 Medium
CVSS3