Linux Kernel up to 6.4.11 regcache.c snd_hdac_regmap_sync null pointer dereference

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5.0	$0-$5k	0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 5.4.254/5.10.191/5.15.127/6.1.46/6.4.11. This impacts the function snd_hdac_regmap_sync of the file drivers/base/regmap/regcache.c. The manipulation leads to null pointer dereference. This vulnerability is uniquely identified as CVE-2023-53275. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.4.254/5.10.191/5.15.127/6.1.46/6.4.11. It has been rated as critical. This issue affects the function snd_hdac_regmap_sync of the file drivers/base/regmap/regcache.c. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ALSA: hda: fix a possible null-pointer dereference due to data race in snd_hdac_regmap_sync() The variable codec->regmap is often protected by the lock codec->regmap_lock when is accessed. However, it is accessed without holding the lock when is accessed in snd_hdac_regmap_sync(): if (codec->regmap) In my opinion, this may be a harmful race, because if codec->regmap is set to NULL right after the condition is checked, a null-pointer dereference can occur in the called function regcache_sync(): map->lock(map->lock_arg); --> Line 360 in drivers/base/regmap/regcache.c To fix this possible null-pointer dereference caused by data race, the mutex_lock coverage is extended to protect the if statement as well as the function call to regcache_sync(). [ Note: the lack of the regmap_lock itself is harmless for the current codec driver implementations, as snd_hdac_regmap_sync() is only for PM runtime resume that is prohibited during the codec probe. But the change makes the whole code more consistent, so it's merged as is -- tiwai ]

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2023-53275 since 09/16/2025. The exploitation is known to be difficult. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 265218 (Linux Distros Unpatched Vulnerability : CVE-2023-53275), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.255, 5.10.192, 5.15.128, 6.1.47 or 6.4.12 eliminates this vulnerability. Applying the patch 109f0aaa0b8838a88af9125b79579023539300a7/9f9eed451176ffcac6b5ba0f6dae1a6b4a1cb0eb/8703b26387e1fa4f8749db98d24c67617b873acb/cdd412b528dee6e0851c4735d6676ec138da13a4/b32e40379e5b2814de0c4bc199edc2d82317dc07/1f4a08fed450db87fbb5ff5105354158bdbe1a22 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 (265218) and CERT Bund (WID-SEC-2025-2053). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• IBM QRadar SIEM
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Dell Secure Connect Gateway
• F5 F5OS

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.4.254
• 5.10.191
• 5.15.127
• 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
• 6.4.0
• 6.4.1
• 6.4.2
• 6.4.3
• 6.4.4
• 6.4.5
• 6.4.6
• 6.4.7
• 6.4.8
• 6.4.9
• 6.4.10
• 6.4.11

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: 5.1
VulDB Meta Temp Score: 5.0

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

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
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: 265218
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-53275

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.4.255/5.10.192/5.15.128/6.1.47/6.4.12
Patch: 109f0aaa0b8838a88af9125b79579023539300a7/9f9eed451176ffcac6b5ba0f6dae1a6b4a1cb0eb/8703b26387e1fa4f8749db98d24c67617b873acb/cdd412b528dee6e0851c4735d6676ec138da13a4/b32e40379e5b2814de0c4bc199edc2d82317dc07/1f4a08fed450db87fbb5ff5105354158bdbe1a22

Timelineinfo

09/16/2025 Advisory disclosed
09/16/2025 +0 days CVE reserved
09/16/2025 +0 days VulDB entry created
01/11/2026 +117 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-53275 (🔒)
GCVE (CVE): GCVE-0-2023-53275
GCVE (VulDB): GCVE-100-324377
CERT Bund: WID-SEC-2025-2053 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 09/16/2025 14:05
Updated: 01/11/2026 09:17
Changes: 09/16/2025 14:05 (59), 09/19/2025 21:09 (2), 12/03/2025 20:19 (11), 12/29/2025 09:03 (7), 01/11/2026 09:17 (1)
Complete: 🔍
Cache ID: 216::103

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

Discussion

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