CVE-2026-6100: Use-after-free in lzma.LZMADecompressor, bz2.BZ2Decompressor, and gzip.GzipFile after re-use under memory pressure

Overview

Severity

High (CVSS 8.1)

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploit Status

Not Exploited

Patch Tuesday

2026-Apr

Released

2026-04-19

Last Updated

2026-08-10

EPSS Score

0.76% (percentile: 54.4%)

Affected Products (4)

Open Source Software

• azl3 python3 3.12.9-10 on Azure Linux 3.0

Other

• 21694-17084
• 21379-17084
• 21492-17084

Revision History

• 2026-04-19: Information published.
• 2026-04-20: Information published.
• 2026-06-03: Information published.
• 2026-06-28: Information published.
• 2026-08-09: Information published.
• 2026-08-10: Information published.