CVE-2025-24294
MEDIUM5.3EPSS 0.27%resolv vulnerable to DoS via insufficient DNS domain name length validation
Published: 7/15/2025Modified: 4/28/2026
Description
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.
Affected packages (4)
- Debian/ruby2.7from 0
- Debian/ruby3.1from 0
- Debian/ruby3.3from 0
- RubyGems/resolvfrom 0, < 0.2.3
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | 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 |
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
References (6)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2025-24294
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2025-24294
- PATCHhttps://github.com/ruby/resolv
- WEBhttps://github.com/ruby/resolv/commit/4c2f71b5e80826506f78417d85b38481c058fb25
- WEBhttps://github.com/rubysec/ruby-advisory-db/blob/master/gems/resolv/CVE-2025-24294.yml
- WEBhttps://www.ruby-lang.org/en/news/2025/07/08/dos-resolv-cve-2025-24294