diff --git a/gems/zlib/CVE-2026-27820.yml b/gems/zlib/CVE-2026-27820.yml
index 17002ecb4a..f4b5c9d50b 100644
--- a/gems/zlib/CVE-2026-27820.yml
+++ b/gems/zlib/CVE-2026-27820.yml
@@ -1,6 +1,7 @@
 ---
 gem: zlib
 cve: 2026-27820
+ghsa: g857-hhfv-j68w
 url: https://www.ruby-lang.org/en/news/2026/03/05/buffer-overflow-zlib-cve-2026-27820
 title: Buffer overflow vulnerability in Zlib::GzipReader
 date: 2026-03-05