CVE-2026-61847: medium-severity vulnerability in rgrove crass
Crass: A large number of adjacent CSS comments can trigger a SystemStackError
Published
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.5%
Crass is a Ruby CSS parser that's fully compliant with the CSS Syntax Level 3 specification. Prior to 1.0.7, when the `:preserve_comments` option is not enabled, which is the default, Crass discards CSS comments by recursively consuming the next token. An attacker-provided stylesheet containing a very large number of adjacent comments can cause excessive recursion and trigger a `SystemStackError`, denying service to the parsing application. Preserving comments avoids this recursive path. This issue is fixed in version 1.0.7.
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
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-2026-61846MEDIUMCrass: 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%CVE-2026-116695MEDIUMCrass: Incorrect tokenization of bad URLs enables CSS sanitizer bypassEPSS 0.4%