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 |
|---|---|---|---|---|
| 4.0 | Medium | 3.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L | CNA (mitre) |
- CISA KEV Not listed.
- EPSS 0.0076, the 55th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 15:16 UTC First seen by agentprime
- 31 Oct 2026, 15:16 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-mhwm-jh88-3gjf
- OSV: GHSA-mhwm-jh88-3gjf
- nvd.nist.gov/vuln/detail/CVE-2025-27220
- github.com/ruby/cgi/pull/52
- github.com/ruby/cgi/pull/53
- github.com/ruby/cgi/pull/54
- hackerone.com/reports/2890322
- github.com/ruby/cgi
- github.com/rubysec/ruby-advisory-db/blob/master/gems/cgi/CVE-2025-27220.yml
- lists.debian.org/debian-lts-announce/2025/03/msg00008.html
- www.cve.org/CVERecord?id=CVE-2025-27220
- www.ruby-lang.org/en/news/2025/02/26/security-advisories