Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Versions of the crass Ruby gem before 1.0.7 are vulnerable. When the default setting that discards comments is in use, a stylesheet containing a very large number of adjacent CSS comments can cause excessive recursion and a SystemStackError, so an attacker who can supply stylesheet input can crash processing. Upgrade to crass 1.0.7, which no longer recurses when discarding comments. Alternatively, set the :preserve_comments option to true, since recursion does not occur when comments are preserved.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 6.3 | Medium | 4.0 | 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 | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0049, the 41st percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:21 UTC First seen by agentprime
- 31 Oct 2026, 14:21 UTC Confirmed by OSV