CVE-2026-116695 (GCVE-0-2026-116695)

Vulnerability from cvelistv5 – Published: 2026-10-27 20:10 – Updated: 2026-10-27 20:10
VLAI
Title
Crass: Incorrect tokenization of bad URLs enables CSS sanitizer bypass
Summary
Crass is a Ruby CSS parser that is compliant with the CSS Syntax Level 3 specification. Prior to 1.0.8, Crass incorrectly treats a closing parenthesis after an escaped backslash as escaped while consuming the remnants of a bad URL. Crass therefore keeps declarations, style rules, or at-rules inside a bad URL token even though a browser treats them as live CSS. A sanitizer that parses untrusted CSS with Crass and reserializes it without rejecting the bad URL can allow CSS used for UI redress, external resource loading, or CSS-based data exfiltration, but this issue does not enable script execution in modern browsers. This issue is fixed in version 1.0.8.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
CWE
  • CWE-436 - Interpretation Conflict
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8035 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
rgrove crass Affected: < 1.0.8
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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          "name": "https://github.com/rgrove/crass/security/advisories/GHSA-pq4g-8rxf-4g29",
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        "discovery": "UNKNOWN"
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      "title": "Crass: Incorrect tokenization of bad URLs enables CSS sanitizer bypass"
    }
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    "datePublished": "2026-10-27T20:10:34.010Z",
    "dateReserved": "2026-10-26T20:00:59.831Z",
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          }
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        "id": "CVE-2026-116695",
        "lastModified": "2026-10-28T15:24:56.033",
        "metrics": {
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      "cve": "CVE-2026-116695",
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      "product_status:known_affected": "3",
      "source": "Red Hat CSAF VEX",
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      "title": "crass: crass: CSS injection via malformed URL token parsing",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-116695.json",
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}



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