cgi Known Vulnerabilities & Fixes
cgi has 5 known security vulnerabilities in RubyGems (Ruby). Upgrade to version 0.4.2 or later to resolve all known issues. Data sourced from OSV, enriched with EPSS exploit probability and CISA KEV.
Low Immediate Risk
No actively exploited vulnerabilities detected. Monitor and update in your next maintenance window.
Recommended safe version: 0.4.2
Upgrading to 0.4.2 or later resolves all 5 known vulnerabilities in cgi. Run: gem install cgi -v 0.4.2
Is cgi in your project?
Check if you're affected and upgrade to 0.4.2 to stay secure.
Security Summary
- 15 affected version ranges have been identified across these 5 advisories.
- 100% of known issues have a published fixed version.
- Remediation: gem update cgi
Vulnerabilities
5 unique vulnerabilities — sorted by exploitation risk (KEV → EPSS → CVSS). Click a CVE/GHSA ID for full details. First disclosed Dec 14, 2021, most recently Mar 3, 2025 (1175 days apart).
| CVE / GHSA | Severity | Affected | Fixed In |
|---|---|---|---|
| CVE-2021-41816 Buffer overrun in CGI.escape_html | CRITICAL | 0.3.0, 0.2.0, 0.1.0 | 0.3.1, 0.2.1, 0.1.0.1 |
| CVE-2021-33621 HTTP response splitting in CGI | HIGH | 0.3.0, 0.3.1, 0.3.2, 0.3.3 (+5 more) | 0.3.5, 0.2.2, 0.1.0.2 |
| CVE-2021-41819 Cookie Prefix Spoofing in CGI::Cookie.parse | HIGH | 0.3.0, 0.2.0, 0.1.0 | 0.3.1, 0.2.1, 0.1.0.1 |
| CVE-2025-27220 CGI has Regular Expression Denial of Service (ReDoS) potential in Util#escapeElement | MEDIUM | 0.1.0, 0.1.0.1, 0.1.0.2, 0.1.1 (+14 more) | 0.3.5.1, 0.3.7, 0.4.2 |
| CVE-2025-27219 CGI has Denial of Service (DoS) potential in Cookie.parse | MEDIUM | 0.1.0, 0.1.0.1, 0.1.0.2, 0.1.1 (+14 more) | 0.3.5.1, 0.3.7, 0.4.2 |
About This Data
Vulnerability data for cgi is sourced from the Open Source Vulnerability (OSV) database, aggregating reports from GitHub Advisory Database, NIST NVD, and ecosystem-specific sources.
CVSS (Common Vulnerability Scoring System) scores reflect exploitability and impact. EPSS (Exploit Prediction Scoring System) scores indicate the probability of exploitation within the next 30 days. Vulnerabilities marked with are listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Related RubyGems (Ruby) Packages
Other packages in this ecosystem, ranked by shared vulnerabilities where available.
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