Описание
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in async decryption Doing an async decryption (large read) crashes with a slab-use-after-free way down in the crypto API. Reproducer:
mount.cifs -o ...,seal,esize=1 //srv/share /mnt
dd if=/mnt/largefile of=/dev/null
...
[ 194.196391] ==================================================================
[ 194.196844] BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xc1/0x110
[ 194.197269] Read of size 8 at addr ffff888112bd0448 by task kworker/u77:2/899
[ 194.197707]
[ 194.197818] CPU: 12 UID: 0 PID: 899 Comm: kworker/u77:2 Not tainted 6.11.0-lku-00028-gfca3ca14a17a-dirty #43
[ 194.198400] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014
[ 194.199046] Workqueue: smb3decryptd smb2_decrypt_offload [cifs]
[ 194.200032] Call Trace:
[ 194.200191]
[ 194.200327] dump_stack_lvl+0x4e/0x70
[ 194.200558] ? gf128mul_4k_lle+0xc1/0x110
[ 194.200809] print_report+0x174/0x505
[ 194.201040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[ 194.201352] ? srso_return_thunk+0x5/0x5f
[ 194.201604] ? __virt_addr_valid+0xdf/0x1c0
[ 194.201868] ? gf128mul_4k_lle+0xc1/0x110
[ 194.202128] kasan_report+0xc8/0x150
[ 194.202361] ? gf128mul_4k_lle+0xc1/0x110
[ 194.202616] gf128mul_4k_lle+0xc1/0x110
[ 194.202863] ghash_update+0x184/0x210
[ 194.203103] shash_ahash_update+0x184/0x2a0
[ 194.203377] ? __pfx_shash_ahash_update+0x10/0x10
[ 194.203651] ? srso_return_thunk+0x5/0x5f
[ 194.203877] ? crypto_gcm_init_common+0x1ba/0x340
[ 194.204142] gcm_hash_assoc_remain_continue+0x10a/0x140
[ 194.204434] crypt_message+0xec1/0x10a0 [cifs]
[ 194.206489] ? __pfx_crypt_message+0x10/0x10 [cifs]
[ 194.208507] ? srso_return_thunk+0x5/0x5f
[ 194.209205] ? srso_return_thunk+0x5/0x5f
[ 194.209925] ? srso_return_thunk+0x5/0x5f
[ 194.210443] ? srso_return_thunk+0x5/0x5f
[ 194.211037] decrypt_raw_data+0x15f/0x250 [cifs]
[ 194.212906] ? __pfx_decrypt_raw_data+0x10/0x10 [cifs]
[ 194.214670] ? srso_return_thunk+0x5/0x5f
[ 194.215193] smb2_decrypt_offload+0x12a/0x6c0 [cifs]
This is because TFM is being used in parallel.
Fix this by allocating a new AEAD TFM for async decryption, but keep
the existing one for synchronous READ cases (similar to what is done
in smb3_calc_signature()).
Also remove the calls to aead_request_set_callback() and
crypto_wait_req() since it's always going to be a synchronous operation.
A flaw was found in the Linux kernel's Server Message Block (SMB) client. An authenticated local attacker with administrative or root privileges could trigger a use-after-free vulnerability during asynchronous decryption of large reads. This flaw could lead to a system crash, resulting in a denial of service (DoS).
Отчет
This issue is considered to be a moderate impact flaw, as the exploitation for this will need an ADMIN (or ROOT) privilege (PR:H).
Меры по смягчению последствий
To mitigate this issue, avoid mounting CIFS shares with the seal and esize=1 options, particularly when interacting with untrusted SMB servers. If these options are necessary, ensure that the SMB share is trusted and properly secured.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 6 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 8 | kernel | Not affected | ||
| Red Hat Enterprise Linux 8 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2025:6966 | 13.05.2025 |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2025:6966 | 13.05.2025 |
Показывать по
Дополнительная информация
Статус:
6.7 Medium
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in async decryption Doing an async decryption (large read) crashes with a slab-use-after-free way down in the crypto API. Reproducer: # mount.cifs -o ...,seal,esize=1 //srv/share /mnt # dd if=/mnt/largefile of=/dev/null ... [ 194.196391] ================================================================== [ 194.196844] BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xc1/0x110 [ 194.197269] Read of size 8 at addr ffff888112bd0448 by task kworker/u77:2/899 [ 194.197707] [ 194.197818] CPU: 12 UID: 0 PID: 899 Comm: kworker/u77:2 Not tainted 6.11.0-lku-00028-gfca3ca14a17a-dirty #43 [ 194.198400] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014 [ 194.199046] Workqueue: smb3decryptd smb2_decrypt_offload [cifs] [ 194.200032] Call Trace: [ 194.200191] <TASK> [ 194.200327] dump_stack_lvl+0x4e/0x70 [ 194.200558] ? gf128mul_4k_lle+0...
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in async decryption Doing an async decryption (large read) crashes with a slab-use-after-free way down in the crypto API. Reproducer: # mount.cifs -o ...,seal,esize=1 //srv/share /mnt # dd if=/mnt/largefile of=/dev/null ... [ 194.196391] ================================================================== [ 194.196844] BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xc1/0x110 [ 194.197269] Read of size 8 at addr ffff888112bd0448 by task kworker/u77:2/899 [ 194.197707] [ 194.197818] CPU: 12 UID: 0 PID: 899 Comm: kworker/u77:2 Not tainted 6.11.0-lku-00028-gfca3ca14a17a-dirty #43 [ 194.198400] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014 [ 194.199046] Workqueue: smb3decryptd smb2_decrypt_offload [cifs] [ 194.200032] Call Trace: [ 194.200191] <TASK> [ 194.200327] dump_sta
In the Linux kernel, the following vulnerability has been resolved: s ...
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in async decryption Doing an async decryption (large read) crashes with a slab-use-after-free way down in the crypto API. Reproducer: # mount.cifs -o ...,seal,esize=1 //srv/share /mnt # dd if=/mnt/largefile of=/dev/null ... [ 194.196391] ================================================================== [ 194.196844] BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xc1/0x110 [ 194.197269] Read of size 8 at addr ffff888112bd0448 by task kworker/u77:2/899 [ 194.197707] [ 194.197818] CPU: 12 UID: 0 PID: 899 Comm: kworker/u77:2 Not tainted 6.11.0-lku-00028-gfca3ca14a17a-dirty #43 [ 194.198400] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014 [ 194.199046] Workqueue: smb3decryptd smb2_decrypt_offload [cifs] [ 194.200032] Call Trace: [ 194.200191] <TASK> [ 194.200327] dump_...
6.7 Medium
CVSS3