Yüksek CVSS 7.8
CVE-2025-21731: Linux Kernel: serbest bırakılmış belleğin kullanımı
Açıklama (NVD)
In the Linux kernel, the following vulnerability has been resolved: nbd: don't allow reconnect after disconnect Following process can cause nbd_config UAF: 1) grab nbd_config temporarily; 2) nbd_genl_disconnect() flush all recv_work() and release the initial reference: nbd_genl_disconnect nbd_disconnect_and_put nbd_disconnect flush_workqueue(nbd->recv_workq) if (test_and_clear_bit(NBD_RT_HAS_CONFIG_REF, ...)) nbd_config_put -> due to step 1), reference is still not zero 3) nbd_genl_reconfigure() queue recv_work() again; nbd_genl_reconfigure config = nbd_get_config_unlocked(nbd) if (!config) -> succeed if (!test_bit(NBD_RT_BOUND, ...)) -> succeed nbd_reconnect_socket queue_work(nbd->recv_workq, &args->work) 4) step 1) release the reference; 5) Finially, recv_work() will trigger UAF: recv_work nbd_config_put(nbd) -> nbd_config is freed atomic_dec(&config->recv_threads) -> UAF Fix the problem by clearing NBD_RT_BOUND in nbd_genl_disconnect(), so that nbd_genl_reconfigure() will fail.
Özet bilgiler
- Ürün
- Linux Linux Kernel
- CVSS v3.1
- 7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS
- %0,24 (yüzdelik 15)
- CWE
- CWE-416
- Yama
- Mevcut
Etkilenen sürümler
| Ürün | Başlangıç | Bitiş | Düzeltildi |
|---|---|---|---|
| linux-linux-kernel | 4.12 | — | 5.4.291 |
| linux-linux-kernel | 5.5 | — | 5.10.235 |
| linux-linux-kernel | 5.11 | — | 5.15.179 |
| linux-linux-kernel | 5.16 | — | 6.1.129 |
| linux-linux-kernel | 6.2 | — | 6.6.76 |
| linux-linux-kernel | 6.7 | — | 6.12.13 |
| linux-linux-kernel | 6.13 | — | 6.13.2 |