CVE-2026-116695: medium-severity vulnerability in rgrove crass
Crass: Incorrect tokenization of bad URLs enables CSS sanitizer bypass
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.3epss 0.4%
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.
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
Affected products
rgrove · crassRelated CVEs — rgrove crass
In the same product, most dangerous first.
CVE-2026-61848MEDIUMCrass: Non-ASCII characters cause superlinear CPU consumptionEPSS 0.5%CVE-2026-61847MEDIUMCrass: A large number of adjacent CSS comments can trigger a SystemStackErrorEPSS 0.5%CVE-2026-61846MEDIUMCrass: Deeply nested CSS blocks and functions can trigger a SystemStackError or excessive memory usageEPSS 0.5%CVE-2026-61845HIGHCrass: Large numeric exponents cause CPU and memory denial of serviceEPSS 0.4%