Crass: Large numeric exponents cause CPU and memory denial of service
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Fix
- Fixed in 1.0.7
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
Crass, a Ruby library for parsing CSS, is affected by this vulnerability. An attacker who supplies a crafted CSS string with an extremely large numeric exponent can make applications using Crass consume excessive CPU and memory, which may crash them.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
Crass is a Ruby CSS parser that's fully compliant with the CSS Syntax Level 3 specification. Prior to 1.0.7, Crass converts `CSS scientific notation` number values with unbounded exponentiation before clamping the result to `Float::MAX`. Applications that use Crass to parse attacker-controlled CSS strings can be forced to spend disproportionate CPU and memory parsing a tiny input, potentially resulting in a crash. This issue is fixed in version 1.0.7.
Timeline
- CVE published
- First seen by cve.now
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- rgrove crass
fixed in 1.0.7
References 3
GitHub · rgrove/crass
Questions about CVE-2026-61845
What does this mean?
Crass is a CSS parser. A tiny CSS input with a large numeric exponent can make it use a disproportionate amount of CPU and memory, which can crash the application that is parsing it.Source: github.com
Am I affected, and how do I check?
Applications that use Crass to parse attacker-controlled CSS strings, on Crass versions before 1.0.7. To check, look at the Crass version the application loads, for example in its dependency lock file or installed gem or package listing.Source: github.com
What should I do about it?
Upgrade Crass to version 1.0.7 or later, which contains the fix.Source: github.com
Is it being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data