VDB
GHSA-g857-hhfv-j68w
GHSA-g857-hhfv-j68w
PUBLISHED
CVSS 9.800000190734863 CRITICAL
Buffer Overflow in Zlib::GzipReader ungetc via large input leads to memory corruption
Risk Scores
CVSS 3.1
9.800000190734863
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| RubyGems | zlib | 3.2.0, 3.1.0, 0 |
Timeline
- Apr 16, 2026 CVE Published
- Apr 30, 2026 Security Advisory
- Jun 10, 2026 CVE Updated
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-27820 advisory
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/zlib/CVE-2026-27820.yml url
- https://github.com/ruby/zlib/security/advisories/GHSA-g857-hhfv-j68w url
- https://hackerone.com/reports/3467067 url
- https://www.ruby-lang.org/en/news/2026/03/05/buffer-overflow-zlib-cve-2026-27820 url
- https://github.com/ruby/zlib package