CVE-2026-54905: concurrent-ruby: `ReentrantReadWriteLock` read-count overflow grants a write lock without exclusivity

Overview

Severity
Medium (CVSS 5.5)
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Exploit Status
Not Exploited
Patch Tuesday
2026-Jun
Released
2026-06-27
Last Updated
2026-06-30
EPSS Score
0.11% (percentile: 1.3%)

Affected Products (1)

Open Source Software

  • azl3 rubygem-concurrent-ruby 1.2.2-1 on Azure Linux 3.0

Revision History

  • 2026-06-27: Information published.
  • 2026-06-29: Information published.
  • 2026-06-30: Information published.