What is CVE-2026-27820?

CVE-2026-27820 is a security advisory published by Microsoft Security Response Center (MSRC) with Low severity. zlib: Buffer Overflow in Zlib::GzipReader ungetc via large input leads to memory corruption

Which CVE IDs does CVE-2026-27820 cover?

CVE-2026-27820 covers the following CVE IDs: CVE-2026-27820. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

Which products are affected by CVE-2026-27820?

CVE-2026-27820 affects 3 products, including: azl3 ruby 3.3.5-7 on Azure Linux 3.0; azl3 ruby 3.3.5-8 on Azure Linux 3.0; azl3 zlib 1.3.2-1 on Azure Linux 3.0.

CVE-2026-27820Low

zlib: Buffer Overflow in Zlib::GzipReader ungetc via large input leads to memory corruption

Vendor

Microsoft Security Response Center (MSRC)

Published

June 2, 2026

Last Modified

—

🔗 CVE IDs covered (1)

CVE-2026-27820 →

🎯 Affected products3

azl3 ruby 3.3.5-7 on Azure Linux 3.0
azl3 ruby 3.3.5-8 on Azure Linux 3.0
azl3 zlib 1.3.2-1 on Azure Linux 3.0

✅ Remediation

KBCBL-Mariner Releases (Security Update) — fixed build 3.3.5-8

🔗 References (2)

advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27820
referencehttps://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade