# CVE-2026-61848: Crass library non-ASCII character parsing DoS

Source: https://junglewise.ai/threats/cve-2026-61848-crass-non-ascii-characters-cause-superlinear-cpu-consumption  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-30. Updated: 2026-10-29  
License: CC BY 4.0 with a link back

CVE-2026-61848 · Severity: medium · CVSS 4 · Published 2026-10-30

Crass is a CSS parsing library used in Ruby applications. When processing attacker-controlled input containing many non-ASCII characters, the library consumes excessive CPU due to inefficient character position tracking, potentially causing denial of service or application hangs.

Technologies: [Rgrove Crass](https://junglewise.ai/threats/technologies/rgrove-crass), [crass (RubyGems)](https://junglewise.ai/threats/technologies/crass). Vendors: [Rgrove](https://junglewise.ai/threats/vendors/rgrove), [RubyGems](https://junglewise.ai/threats/vendors/rubygems).

## Quick answers

**Is CVE-2026-61848 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-61848 being exploited in the wild.

**How severe is CVE-2026-61848?** Medium severity, with a CVSS score of 4, published 30 October 2026.

**Which products and versions are affected?** Rgrove Crass < 1.0.7; crass (RubyGems) < 1.0.7, ECOSYSTEM:introduced=0,fixed=1.0.7.

**Is there a fix for CVE-2026-61848?** Yes. crass (RubyGems): upgrade to 1.0.7 or later. Until then: Avoid passing non-ASCII input to Crass, or filter and sanitize user input to contain only ASCII characters before passing to the library. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-61848 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-61848?** Check whether you run Rgrove Crass or crass (RubyGems) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- crass (RubyGems): upgrade to 1.0.7 or later

  ```sh
  bundle update crass
  ```


Avoid passing non-ASCII input to Crass, or filter and sanitize user input to contain only ASCII characters before passing to the library.

## Technical details

Crass exhibits superlinear CPU consumption when parsing inputs with non-ASCII characters due to inefficient tracking of multi-byte character positions. An attacker can craft malicious input containing many non-ASCII characters to trigger this behavior via network or local input vectors. The vulnerability allows denial of service through resource exhaustion without requiring authentication or user interaction.

## Affected products

- rgrove Crass < 1.0.7

## Identifiers

- CVE-2026-61848
- GHSA-8vfg-2r28-hvhj

## Timeline

- 2026-10-29: disclosed

## References

- [https://api.github.com/users/hourianto](https://api.github.com/users/hourianto)

## Related threats

- [Crass CSS parser stack overflow via excessive comments](https://junglewise.ai/threats/cve-2026-61847-crass-a-large-number-of-adjacent-css-comments-can-trigger-a)
- [Crass CSS parser uncontrolled recursion denial of service](https://junglewise.ai/threats/cve-2026-61846-crass-deeply-nested-css-blocks-and-functions-can-trigger-a)
- [Crass CSS parser denial of service via large numeric exponents](https://junglewise.ai/threats/cve-2026-61845-crass-large-numeric-exponents-cause-cpu-and-memory-denial-of)
- [Crass CSS parser bad URL tokenizer bypass in sanitizers](https://junglewise.ai/threats/cve-2026-116695-crass-is-a-ruby-css-parser-that-is-compliant-with-the-css-syntax)