CVE-2024-50047 - Vulnerability Details

- smb: client: fix UAF in async decryption

Description

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+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.

Published: 2024-10-21

Score: 7.8 High

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Linux

unaffected

Version	Status	Constraints
`35cf94a397280b9e27576ac1480f631bdd3e7b70`	affected	< 8f14a476abba13144df5434871a7225fd29af633
`35cf94a397280b9e27576ac1480f631bdd3e7b70`	affected	< ef51c0d544b1518b35364480317ab6d3468f205d
`35cf94a397280b9e27576ac1480f631bdd3e7b70`	affected	< bce966530fd5542bbb422cb45ecb775f7a1a6bc3
`35cf94a397280b9e27576ac1480f631bdd3e7b70`	affected	< 0809fb86ad13b29e1d6d491364fc7ea4fb545995
`35cf94a397280b9e27576ac1480f631bdd3e7b70`	affected	< 538c26d9bf70c90edc460d18c81008a4e555925a
`35cf94a397280b9e27576ac1480f631bdd3e7b70`	affected	< b0abcd65ec545701b8793e12bc27dc98042b151a

Linux

affected

Version	Status	Constraints
`5.4`	affected	—
`0`	unaffected	< 5.4
`5.10.237`	unaffected	≤ 5.10.*
`5.15.181`	unaffected	≤ 5.15.*
`6.1.128`	unaffected	≤ 6.1.*
`6.6.57`	unaffected	≤ 6.6.*
`6.11.4`	unaffected	≤ 6.11.*
`6.12`	unaffected	≤ *

Configuration 1 [-]

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

Package	CPE	Advisory	Released Date
Red Hat Enterprise Linux 9
kernel-0:5.14.0-570.12.1.el9_6	cpe:/a:redhat:enterprise_linux:9	RHSA-2025:6966	2025-05-13T00:00:00Z
kernel-0:5.14.0-570.12.1.el9_6	cpe:/o:redhat:enterprise_linux:9	RHSA-2025:6966	2025-05-13T00:00:00Z

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
Debian DLA	DLA-4076-1	linux-6.1 security update
Debian DLA	DLA-4178-1	linux security update
Ubuntu USN	USN-7276-1	Linux kernel vulnerabilities
Ubuntu USN	USN-7277-1	Linux kernel vulnerabilities
Ubuntu USN	USN-7310-1	Linux kernel vulnerabilities
Ubuntu USN	USN-7383-1	Linux kernel vulnerabilities
Ubuntu USN	USN-7383-2	Linux kernel (Real-time) vulnerabilities
Ubuntu USN	USN-7384-1	Linux kernel (Azure) vulnerabilities
Ubuntu USN	USN-7384-2	Linux kernel (Azure) vulnerabilities
Ubuntu USN	USN-7385-1	Linux kernel (IBM) vulnerabilities
Ubuntu USN	USN-7386-1	Linux kernel (OEM) vulnerabilities
Ubuntu USN	USN-7403-1	Linux kernel (HWE) vulnerabilities
Ubuntu USN	USN-7451-1	Linux kernel vulnerabilities
Ubuntu USN	USN-7468-1	Linux kernel (Azure, N-Series) vulnerabilities
Ubuntu USN	USN-7523-1	Linux kernel (Raspberry Pi Real-time) vulnerabilities
Ubuntu USN	USN-7524-1	Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN	USN-7608-1	Linux kernel vulnerabilities
Ubuntu USN	USN-7608-2	Linux kernel (FIPS) vulnerabilities
Ubuntu USN	USN-7608-3	Linux kernel (Real-time) vulnerabilities
Ubuntu USN	USN-7608-4	Linux kernel vulnerabilities
Ubuntu USN	USN-7608-5	Linux kernel vulnerabilities
Ubuntu USN	USN-7608-6	Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN	USN-7608-7	Linux kernel (Azure) vulnerabilities
Ubuntu USN	USN-7655-1	Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN	USN-7671-1	Linux kernel vulnerabilities
Ubuntu USN	USN-7671-2	Linux kernel vulnerabilities
Ubuntu USN	USN-7671-3	Linux kernel (IoT) vulnerabilities
Ubuntu USN	USN-7686-1	Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN	USN-7712-1	Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN	USN-7712-2	Linux kernel (Azure) vulnerabilities

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00019.

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://git.kernel.org/stable/c/0809fb86ad13b29e1d6d491364fc7ea4fb545995
https://git.kernel.org/stable/c/538c26d9bf70c90edc460d18c81008a4e555925a
https://git.kernel.org/stable/c/8f14a476abba13144df5434871a7225fd29af633
https://git.kernel.org/stable/c/b0abcd65ec545701b8793e12bc27dc98042b151a
https://git.kernel.org/stable/c/bce966530fd5542bbb422cb45ecb775f7a1a6bc3
https://git.kernel.org/stable/c/ef51c0d544b1518b35364480317ab6d3468f205d
https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html
https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
https://lore.kernel.org/linux-cve-announce/2024102134-CVE-2024-50047-7a27@gregkh/T
https://nvd.nist.gov/vuln/detail/CVE-2024-50047
https://www.cve.org/CVERecord?id=CVE-2024-50047

History

Mon, 03 Nov 2025 21:30:00 +0000

Type	Values Removed	Values Added
References		https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html

Mon, 03 Nov 2025 20:30:00 +0000

Type	Values Removed	Values Added
References		https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html

Wed, 16 Jul 2025 13:45:00 +0000

Type	Values Removed	Values Added
Metrics	epss `{'score': 0.00032}`	epss `{'score': 0.00033}`

Wed, 14 May 2025 02:30:00 +0000

Type	Values Removed	Values Added
First Time appeared		Redhat Redhat enterprise Linux
CPEs		cpe:/a:redhat:enterprise_linux:9 cpe:/o:redhat:enterprise_linux:9
Vendors & Products		Redhat Redhat enterprise Linux

Fri, 02 May 2025 06:30:00 +0000

Type	Values Removed	Values Added
References		https://git.kernel.org/stable/c/8f14a476abba13144df5434871a7225fd29af633 https://git.kernel.org/stable/c/ef51c0d544b1518b35364480317ab6d3468f205d

Sun, 02 Feb 2025 10:30:00 +0000

Type	Values Removed	Values Added
References		https://git.kernel.org/stable/c/bce966530fd5542bbb422cb45ecb775f7a1a6bc3

Wed, 23 Oct 2024 22:45:00 +0000

Type	Values Removed	Values Added
First Time appeared		Linux Linux linux Kernel
Weaknesses		CWE-416
CPEs		cpe:2.3:o:linux:linux_kernel::::::::
Vendors & Products		Linux Linux linux Kernel
Metrics	cvssV3_1 `{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}`	cvssV3_1 `{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}`

Wed, 23 Oct 2024 01:30:00 +0000

Type	Values Removed	Values Added
References		https://lore.kernel.org/linux-cve-announce/2024102134-CVE-2024-50047-7a27@gregkh/T https://nvd.nist.gov/vuln/detail/CVE-2024-50047 https://www.cve.org/CVERecord?id=CVE-2024-50047
Metrics	threat_severity `None`	cvssV3_1 `{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}` threat_severity `Moderate`

Tue, 22 Oct 2024 14:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 21 Oct 2024 19:45:00 +0000

Type	Values Removed	Values Added
Description		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+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.
Title		smb: client: fix UAF in async decryption
References		https://git.kernel.org/stable/c/0809fb86ad13b29e1d6d491364fc7ea4fb545995 https://git.kernel.org/stable/c/538c26d9bf70c90edc460d18c81008a4e555925a https://git.kernel.org/stable/c/b0abcd65ec545701b8793e12bc27dc98042b151a

Subscriptions

Linux Linux Kernel

Redhat Enterprise Linux

MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-10-21T19:39:44.430Z

Updated: 2026-05-11T20:44:28.155Z

Reserved: 2024-10-21T12:17:06.071Z

Link: CVE-2024-50047

Vulnrichment

Updated: 2025-11-03T20:43:16.334Z

NVD

Status : Modified

Published: 2024-10-21T20:15:17.507

Modified: 2025-11-03T21:16:55.063

Link: CVE-2024-50047

Redhat

Severity : Moderate

Publid Date: 2024-10-21T00:00:00Z

Links: CVE-2024-50047 - Bugzilla

OpenCVE Enrichment

No data.

Weaknesses

CWE-416

Tracking

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

Exploitation none

Automatable no

Technical Impact partial

Subscriptions

JSON object

JSON object

JSON object

JSON object

JSON object