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...

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...

GHSA-6WX8-W4F5-WWCR 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...

Concurrent Ruby: `ReentrantReadWriteLock` read-count overflow grants a write lock without exclusivity

Summary Concurrent::ReentrantReadWriteLock can incorrectly grant a write lock after one thread acquires the read lock 32,768 times. The lock stores a thread's local read and write hold counts in one integer. The low 15 bits are used for the read hold count, and bit 15 is used as WRITELOCKHELD...

Wrap-around Error

Overview Affected versions of this package are vulnerable to Wrap-around Error in ReentrantReadWriteLock that causes incorrect write locks. An attacker can cause a thread to incorrectly obtain a write lock without exclusivity by repeatedly acquiring the read lock 32,768 times, which overflows the...

GHSA-WV3X-4VXV-WHPP Concurrent Ruby: `ReentrantReadWriteLock` read-count overflow grants a write lock without exclusivity

Summary Concurrent::ReentrantReadWriteLock can incorrectly grant a write lock after one thread acquires the read lock 32,768 times. The lock stores a thread's local read and write hold counts in one integer. The low 15 bits are used for the read hold count, and bit 15 is used as WRITELOCKHELD...

Infinite loop

Overview Affected versions of this package are vulnerable to Infinite loop in the AtomicReferenceupdate function when the current value is Float::NAN. An attacker can cause indefinite busy retry loops and CPU exhaustion by supplying malicious numeric data. Remediation Upgrade concurrent-ruby to...

kernel: ALSA: aloop: Fix peer runtime UAF during format-change stop

A flaw was found in the Linux kernel's ALSA Advanced Linux Sound Architecture aloop driver. This Use-After-Free UAF vulnerability occurs when loopbackcheckformat stops the capture side during a format change, while a concurrent close operation detaches or frees the runtime. An attacker could...

Concurrent Ruby - `AtomicReference#update` livelocks when the stored value is `Float::NAN`

Summary Concurrent::AtomicReferenceupdate can enter a permanent busy retry loop when the current value is Float::NAN. The issue is caused by the interaction between: - AtomicReferenceupdate, which retries until compareandsetoldvalue, newvalue succeeds. - Numeric compareandset, which checks old ==...

Concurrent Ruby - `ReentrantReadWriteLock` read-count overflow grants a write lock without exclusivity

Summary Concurrent::ReentrantReadWriteLock can incorrectly grant a write lock after one thread acquires the read lock 32,768 times. The lock stores a thread's local read and write hold counts in one integer. The low 15 bits are used for the read hold count, and bit 15 is used as WRITELOCKHELD...

PT-2026-51091

Name of the Vulnerable Software and Affected Versions concurrent-ruby versions prior to 1.3.7 Description Concurrent::ReentrantReadWriteLock can incorrectly grant a write lock after a single thread acquires the read lock 32,768 times. The lock manages a thread's local read and write hold counts...

CVE-2026-48982 pam_usb: Missing O_EXCL on pad temp file creation allows concurrent update race

pamusb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, when updating a one-time pad file, a temporary file is created using open without the OEXCL flag. Without OEXCL, the create operation is not atomic: two concurrent processes racing to...

CVE-2026-48982 pam_usb: Missing O_EXCL on pad temp file creation allows concurrent update race

pamusb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, when updating a one-time pad file, a temporary file is created using open without the OEXCL flag. Without OEXCL, the create operation is not atomic: two concurrent processes racing to...

CVE-2026-48982

CVE-2026-48982 affects pam_usb prior to version 0.9.2, where updating a one-time pad file creates a temporary file with open() lacking O_EXCL, enabling a race between concurrent processes to update the same pad. This non-atomicity can cause the stored pad to diverge from expectations, potentially...

CVE-2026-11791

A flaw was found in 389 Directory Server. During schema reload, the attrsyntaxswapht function unconditionally frees attribute syntax information nodes, bypassing the refcount-based deferred deletion used elsewhere in the attribute syntax subsystem. If an administrator triggers schema reload while...

EUVD-2026-37902

A flaw was found in 389 Directory Server. During schema reload, the attrsyntaxswapht function unconditionally frees attribute syntax information nodes, bypassing the refcount-based deferred deletion used elsewhere in the attribute syntax subsystem. If an administrator triggers schema reload while...

CVE-2026-11791

A flaw was found in 389 Directory Server. During schema reload, the attrsyntaxswapht function unconditionally frees attribute syntax information nodes, bypassing the refcount-based deferred deletion used elsewhere in the attribute syntax subsystem. If an administrator triggers schema reload while...

CVE-2026-11791

The CVE-2026-11791 entry concerns 389 Directory Server (389-ds-base), where during schema reload the attr_syntax_swap_ht() function unconditionally frees attribute syntax information nodes, bypassing refcount-based deferred deletion. This can lead to use-after-free or double-free when LDAP query ...

CVE-2026-54224

UBB.threads is affected by a Denial of Service described in CVE-2026-54224. An authenticated attacker can trigger DoS by issuing multiple concurrent requests to view user profiles on instances with many registered users, exhausting database resources and denying access to the application for othe...

netty-codec-http2: Netty: Denial of Service via uncontrolled HTTP/2 concurrent streams

A flaw was found in Netty, a network application framework. A remote attacker can exploit this vulnerability by sending a large number of HTTP/2 stream requests to a Netty HTTP/2 server. If the server does not explicitly limit concurrent streams, it can lead to the allocation of numerous long-liv...