# concurrent-ruby (RubyGems) vulnerabilities

3 known vulnerabilities (1 high, 2 low), with the versions each affects and the releases that fix them.

## At a glance

- Latest release: not known (cve.now hasn't read this package's releases)
- Newest unaffected release: not known without release data
- Registry: https://rubygems.org/gems/concurrent-ruby

## Advisories (3)

### [CVE-2026-54906](https://cve.now/CVE-2026-54906): concurrent-ruby: ReadWriteLock allows wrong-thread write release and stray read-release counter corruption

- Severity: Low 2.1
- Published: Jun 24, 2026
- Affected: fixed in 1.3.7.

### [CVE-2026-54904](https://cve.now/CVE-2026-54904): concurrent-ruby: \`AtomicReference#update\` livelocks when the stored value is \`Float::NAN\`

- Severity: High 8.2
- Published: Jun 24, 2026
- Affected: fixed in 1.3.7.

### [CVE-2026-54905](https://cve.now/CVE-2026-54905): concurrent-ruby: \`ReentrantReadWriteLock\` read-count overflow grants a write lock without exclusivity

- Severity: Low 2.0
- Published: Jun 24, 2026
- Affected: fixed in 1.3.7.

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