VDB
CVE-2026-27820
CVE-2026-27820
PUBLISHED
CVSS 1.7000000476837158 LOW
Buffer Overflow in Zlib::GzipReader ungetc via large input leads to memory corruption
EPSS 0.02% · 4.3th percentile
Risk Scores
CVSS 4.0
1.7000000476837158
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U
EPSS Score
0.02%
4.3th percentile
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| RubyGems | zlib | 0, 3.2.0, 3.1.0 |
| ruby | zlib | < 3.0.1, >= 3.1.0, < 3.1.2, >= 3.2.0, < 3.2.3 |
Exploit Intelligence
- https://hackerone.com/reports/3467067 (nist-nvd)
- CIRCL seen: CVE-2026-27820 (circl-sighting)
- CIRCL seen: CVE-2026-27820 (circl-sighting)
- CIRCL seen: CVE-2026-27820 (circl-sighting)
- https://github.com/ruby/zlib/security/advisories/GHSA-g857-hhfv-j68w (circl)
- setup.sh (github-poc)
- setup.sh (github-poc)
- setup.sh (github-poc)
- setup.sh (github-poc)
- setup.sh (github-poc)
…and 1 more exploits
Timeline
- Mar 5, 2026 PoC Published
- Mar 5, 2026 PoC Published
- Mar 6, 2026 PoC Published
- Apr 16, 2026 CVE Published
- Apr 17, 2026 Security Advisory
- May 18, 2026 EPSS Score
- May 19, 2026 EPSS Score
- May 20, 2026 EPSS Score
- May 21, 2026 EPSS Score
- May 21, 2026 CVE Updated
- May 22, 2026 EPSS Score
- May 23, 2026 EPSS Score
References
- https://github.com/ruby/zlib/security/advisories/GHSA-g857-hhfv-j68w url
- https://hackerone.com/reports/3467067 url
- https://nvd.nist.gov/vuln/detail/CVE-2026-27820 advisory
- https://github.com/ruby/zlib package
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/zlib/CVE-2026-27820.yml url
- https://www.ruby-lang.org/en/news/2026/03/05/buffer-overflow-zlib-cve-2026-27820 url