Linux Kernel up to 6.5.3 kcm net/core/skbuff.c kcm_sendmsg memory leak

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4.6	$0-$5k	0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.5.3 and classified as critical. The impacted element is the function kcm_sendmsg of the file net/core/skbuff.c of the component kcm. This manipulation causes memory leak. This vulnerability is tracked as CVE-2023-54112. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.5.3. Affected by this vulnerability is the function kcm_sendmsg of the file net/core/skbuff.c of the component kcm. The manipulation with an unknown input leads to a memory leak vulnerability. The CWE definition for the vulnerability is CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: kcm: Fix memory leak in error path of kcm_sendmsg() syzbot reported a memory leak like below: BUG: memory leak unreferenced object 0xffff88810b088c00 (size 240): comm "syz-executor186", pid 5012, jiffies 4294943306 (age 13.680s) hex dump (first 32 bytes): 00 89 08 0b 81 88 ff ff 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff83e5d5ff>] __alloc_skb+0x1ef/0x230 net/core/skbuff.c:634 [<ffffffff84606e59>] alloc_skb include/linux/skbuff.h:1289 [inline] [<ffffffff84606e59>] kcm_sendmsg+0x269/0x1050 net/kcm/kcmsock.c:815 [<ffffffff83e479c6>] sock_sendmsg_nosec net/socket.c:725 [inline] [<ffffffff83e479c6>] sock_sendmsg+0x56/0xb0 net/socket.c:748 [<ffffffff83e47f55>] ____sys_sendmsg+0x365/0x470 net/socket.c:2494 [<ffffffff83e4c389>] ___sys_sendmsg+0xc9/0x130 net/socket.c:2548 [<ffffffff83e4c536>] __sys_sendmsg+0xa6/0x120 net/socket.c:2577 [<ffffffff84ad7bb8>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff84ad7bb8>] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 [<ffffffff84c0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd In kcm_sendmsg(), kcm_tx_msg(head)->last_skb is used as a cursor to append newly allocated skbs to 'head'. If some bytes are copied, an error occurred, and jumped to out_error label, 'last_skb' is left unmodified. A later kcm_sendmsg() will use an obsoleted 'last_skb' reference, corrupting the 'head' frag_list and causing the leak. This patch fixes this issue by properly updating the last allocated skb in 'last_skb'.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2023-54112 since 12/24/2025. The exploitation appears to be difficult. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 280025 (Linux Distros Unpatched Vulnerability : CVE-2023-54112), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.326, 4.19.295, 5.4.257, 5.10.195, 5.15.132, 6.1.54 or 6.5.4 eliminates this vulnerability. Applying the patch 8dc7eb757b1652b82725f32e0c89a1e9f6c0e13b/5e5554389397e98fafb9efe395d8b4830dd5f042/479c71cda14b3c3a6515773faa39055333eaa2b7/33db24ad811b3576a0c2f8862506763f2be925b0/97275339c34cfbccd65e87bc38fd910ae66c48ba/16989de75497574b5fafd174c0c233d5a86858b7/af8085e0fc3207ecbf8b9e7a635c790e36d058c6/c821a88bd720b0046433173185fd841a100d44ad is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (280025) and CERT Bund (WID-SEC-2025-2929). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Open Source Linux Kernel

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.14.325
• 4.19.294
• 5.4.256
• 5.10.194
• 5.15.131
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.1.30
• 6.1.31
• 6.1.32
• 6.1.33
• 6.1.34
• 6.1.35
• 6.1.36
• 6.1.37
• 6.1.38
• 6.1.39
• 6.1.40
• 6.1.41
• 6.1.42
• 6.1.43
• 6.1.44
• 6.1.45
• 6.1.46
• 6.1.47
• 6.1.48
• 6.1.49
• 6.1.50
• 6.1.51
• 6.1.52
• 6.1.53
• 6.5.0
• 6.5.1
• 6.5.2
• 6.5.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
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CPE 2.2info

• 🔒
• 🔒
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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.6

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory leak
CWE: CWE-401 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 280025
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-54112

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 4.14.326/4.19.295/5.4.257/5.10.195/5.15.132/6.1.54/6.5.4
Patch: 8dc7eb757b1652b82725f32e0c89a1e9f6c0e13b/5e5554389397e98fafb9efe395d8b4830dd5f042/479c71cda14b3c3a6515773faa39055333eaa2b7/33db24ad811b3576a0c2f8862506763f2be925b0/97275339c34cfbccd65e87bc38fd910ae66c48ba/16989de75497574b5fafd174c0c233d5a86858b7/af8085e0fc3207ecbf8b9e7a635c790e36d058c6/c821a88bd720b0046433173185fd841a100d44ad

Timelineinfo

12/24/2025 Advisory disclosed
12/24/2025 +0 days CVE reserved
12/24/2025 +0 days VulDB entry created
01/03/2026 +10 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-54112 (🔒)
GCVE (CVE): GCVE-0-2023-54112
GCVE (VulDB): GCVE-100-338257
CERT Bund: WID-SEC-2025-2929 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 12/24/2025 16:37
Updated: 01/03/2026 04:01
Changes: 12/24/2025 16:37 (60), 12/25/2025 14:50 (1), 12/27/2025 14:29 (2), 01/03/2026 04:01 (7)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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