GHSA-xh69-987w-hrp8
resolv vulnerable to DoS via insufficient DNS domain name length validation
At a glance
- Published
- Updated
- CVE
- CVE-2025-24294
- CVSS_V3
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- CVSS_V4
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Description
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)
Affected packages
| Package | Versions |
|---|---|
| RubyGems · resolv | introduced 0, fixed 0.2.3 |
| RubyGems · resolv | introduced 0.4.0, fixed 0.6.2 |
| RubyGems · resolv | introduced 0.3.0, fixed 0.3.1 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2025-24294 ADVISORY
- https://github.com/ruby/resolv/commit/4c2f71b5e80826506f78417d85b38481c058fb25 WEB
- https://github.com/ruby/resolv PACKAGE
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/resolv/CVE-2025-24294.yml WEB
- https://www.ruby-lang.org/en/news/2025/07/08/dos-resolv-cve-2025-24294 WEB
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |