Import Source
https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-90620.json
JSON Data
https://api.osv.dev/v1/vulns/AZL-90620
Upstream
Published
2026-06-25T09:16:33Z
Modified
2026-08-28T17:48:06.093516030Z
Summary
CVE-2026-53163 affecting package kernel for versions less than 6.6.144.1-1
Details

In the Linux kernel, the following vulnerability has been resolved:

locking/rtmutex: Skip remove_waiter() when waiter is not enqueued

syzbot triggered the following splat in removewaiter() via FUTEXCMPREQUEUEPI:

KASAN: null-ptr-deref in range [0x0000000000000a88-0x0000000000000a8f] classrawspinlockconstructor removewaiter+0x159/0x1200 kernel/locking/rtmutex.c:1561 rtmutexstartproxylock+0x103/0x120 futex_requeue+0x10e4/0x20d0 __x64sysfutex+0x34f/0x4d0

taskblocksonrtmutex() does not arm the waiter upon deadlock detection, leaving waiter->task nil, where 3bfdc63936dd ("rtmutex: Use waiter::task instead of current in remove_waiter()") made this fatal.

Furthermore, rtmutexstartproxylock() should not be calling into removewaiter() upon a successfully grabbing the rtmutex. 1a1fb985f2e2 ("futex: Handle early deadlock return correctly"), moved the removewaiter() out of __rtmutexstartproxylock() (where 'ret' was only ever 0 or < 0) into the wrapper. Tighten this check to account for trytotakertmutex().

References

Affected packages

Azure Linux:3 / kernel

Package

Name
kernel
Purl
pkg:rpm/azure-linux/kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
6.6.144.1-1

Database specific

source
"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-90620.json"