CVE-2026-54906
LOW
INFO
Priority: 0.00
BB Relevance:
39/100
Published: 2026-06-24
Modified: 2026-10-25
First seen: 2026-10-29
Status: active
Attack Surface
Low Complexity
No Auth
No Interaction
CVSS Vector Breakdown
AV:
Local
AC:
High
PR:
None
UI:
None
S:
X
AT:
None
VC:
None
VI:
Low
VA:
Low
Description
concurrent-ruby is a modern concurrency tools for Ruby. Prior to 1.3.7, Concurrent::ReadWriteLock#release_write_lock 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 running. Concurrent::ReadWriteLock#release_read_lock also decrements the shared counter even when no read lock is held. Calling it on a fresh lock changes the counter from 0 to -1, after which normal read acquisition raises Concurrent::ResourceLimitError. This is a synchronization correctness issue in the public Concurrent::ReadWriteLock API. This vulnerability is fixed in 1.3.7.
Affected Software (1)
| Vendor | Product | Version |
|---|---|---|
| rubyconcurrency | concurrent_ruby | < 1.3.7 |
References & Advisories (1)
Third Party Advisory