Vulnerability · Published Oct 30, 2026 · Assigned by GitHub_M
CVE-2026-61848Crass: Non-ASCII characters cause superlinear CPU consumption
Medium 6.3
In plain English
A medium-severity uncontrolled resource consumption in crass from rgrove. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Crass is a Ruby CSS parser that's fully compliant with the CSS Syntax Level 3 specification. Prior to 1.0.7, when Crass parses input containing `non-ASCII characters`, inefficiencies in tracking the positions of `multi-byte characters` result in superlinear parsing time. An attacker-controlled CSS input consisting of many `non-ASCII characters` can therefore cause excessive CPU consumption and potentially denial of service. This issue is fixed in version 1.0.7.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | ruby-crass | no fix listed | DEBIAN-CVE-2026-61848 |
| Debian:13 | ruby-crass | no fix listed | DEBIAN-CVE-2026-61848 |
| Debian:14 | ruby-crass | 1.0.7-1 | DEBIAN-CVE-2026-61848 |
| RubyGems | crass | 1.0.7 | GHSA-8vfg-2r28-hvhj |
| Ubuntu:22.04:LTS | ruby-crass | no fix listed | UBUNTU-CVE-2026-61848 |
| Ubuntu:24.04:LTS | ruby-crass | no fix listed | UBUNTU-CVE-2026-61848 |
| Ubuntu:26.04:LTS | ruby-crass | no fix listed | UBUNTU-CVE-2026-61848 |
| Ubuntu:26.10 | ruby-crass | no fix listed | UBUNTU-CVE-2026-61848 |
Affected products (as reported)
Weakness: CWE-400 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L
References
- https://github.com/rgrove/crass/security/advisories/GHSA-8vfg-2r28-hvhj x_refsource_CONFIRM
- https://github.com/rgrove/crass/releases/tag/v1.0.7 x_refsource_MISC
- http://github.com/rgrove/crass/commit/da29664648bf80a97a6439e030a4814291c9afa5 x_refsource_MISC