CVE-2026-54906

concurrent-ruby is a modern concurrency tools for Ruby. Prior to 1.3.7, Concurrent::ReadWriteLockreleasewritelock does not verify that the calling thread acquired the write lock. Any thread with access to the lock object can release an active write lock held by another thread. A second writer can...

Improper Locking

Overview Affected versions of this package are vulnerable to Improper Locking in the releasewritelock and releasereadlock functions. An attacker can disrupt synchronization guarantees and exploit data races or cause denial of service by invoking these functions from unauthorized threads or withou...

Concurrent Ruby - ReadWriteLock allows wrong-thread write release and stray read-release counter corruption

Summary Concurrent::ReadWriteLockreleasewritelock does not verify that the calling thread acquired the write lock. Any thread with access to the lock object can release an active write lock held by another thread. A second writer can then enter its critical section while the first writer is still...