Описание
In the Linux kernel, the following vulnerability has been resolved:
security/keys: fix missed RCU read section on lookup
Nicholas Carlini reports that the keyring code calls assoc_array_find()
in find_key_to_update() without holding the RCU read lock, while the
assoc_array_gc() code really is designed around removing the node from
the tree and then freeing it after an RCU grace-period.
The regular key handling doesn't see this because holding the keyring
semaphore hides any lifetime issues, but the persistent key handling
uses a different model.
Instead of extending the keyring locking, just do the simple RCU locking
that the assoc_array was designed for.
A flaw was found in the Linux kernel's keyring code. The assoc_array_find() function, used for looking up keys, was called without holding the necessary Read-Copy-Update (RCU) read lock. This oversight allows for a memory corruption vulnerability, particularly affecting persistent key handling, as the system's garbage collection mechanism can free memory while it is still in use. This could lead to a denial of service.
Отчет
This vulnerability is evaluated as a Moderate severity issue because exploitation requires an authenticated local user and winning a narrow race condition against kernel memory reclamation. While standard Red Hat Enterprise Linux installations enable kernel keyring functionality by default, triggering the underlying memory corruption necessitates concurrent persistent key lookups and garbage collection. Consequently, the flaw primarily poses a local denial of service or privilege escalation risk under specific operational concurrency.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 6 | kernel | Out of support scope | ||
| Red Hat Enterprise Linux 7 | kernel | Affected | ||
| Red Hat Enterprise Linux 7 | kernel-rt | Affected | ||
| Red Hat Enterprise Linux 9 | kernel-rt | Affected | ||
| Red Hat Enterprise Linux 10 | kernel | Fixed | RHSA-2026:65334 | 08.09.2026 |
| Red Hat Enterprise Linux 8 | kernel-rt | Fixed | RHSA-2026:66324 | 10.09.2026 |
| Red Hat Enterprise Linux 8 | kernel | Fixed | RHSA-2026:66325 | 10.09.2026 |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2026:67470 | 15.09.2026 |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2026:67470 | 15.09.2026 |
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Дополнительная информация
Статус:
7 High
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: security/keys: fix missed RCU read section on lookup Nicholas Carlini reports that the keyring code calls assoc_array_find() in find_key_to_update() without holding the RCU read lock, while the assoc_array_gc() code really is designed around removing the node from the tree and then freeing it after an RCU grace-period. The regular key handling doesn't see this because holding the keyring semaphore hides any lifetime issues, but the persistent key handling uses a different model. Instead of extending the keyring locking, just do the simple RCU locking that the assoc_array was designed for.
In the Linux kernel, the following vulnerability has been resolved: security/keys: fix missed RCU read section on lookup Nicholas Carlini reports that the keyring code calls assoc_array_find() in find_key_to_update() without holding the RCU read lock, while the assoc_array_gc() code really is designed around removing the node from the tree and then freeing it after an RCU grace-period. The regular key handling doesn't see this because holding the keyring semaphore hides any lifetime issues, but the persistent key handling uses a different model. Instead of extending the keyring locking, just do the simple RCU locking that the assoc_array was designed for.
In the Linux kernel, the following vulnerability has been resolved: s ...
7 High
CVSS3