Linux Kernel up to 6.19.8 hwmon bin2hex buffer overflow

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7.5	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.19.8. It has been rated as critical. Affected by this issue is the function bin2hex of the component hwmon. Performing a manipulation results in buffer overflow. This vulnerability is reported as CVE-2026-43380. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.19.8. This affects the function bin2hex of the component hwmon. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus/q54sj108a2) fix stack overflow in debugfs read The q54sj108a2_debugfs_read function suffers from a stack buffer overflow due to incorrect arguments passed to bin2hex(). The function currently passes 'data' as the destination and 'data_char' as the source. Because bin2hex() converts each input byte into two hex characters, a 32-byte block read results in 64 bytes of output. Since 'data' is only 34 bytes (I2C_SMBUS_BLOCK_MAX + 2), this writes 30 bytes past the end of the buffer onto the stack. Additionally, the arguments were swapped: it was reading from the zero-initialized 'data_char' and writing to 'data', resulting in all-zero output regardless of the actual I2C read. Fix this by: 1. Expanding 'data_char' to 66 bytes to safely hold the hex output. 2. Correcting the bin2hex() argument order and using the actual read count. 3. Using a pointer to select the correct output buffer for the final simple_read_from_buffer call.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-43380 since 05/01/2026. The exploitability is told to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/22/2026).

The vulnerability scanner Nessus provides a plugin with the ID 315719 (Linux Distros Unpatched Vulnerability : CVE-2026-43380), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.203, 6.1.167, 6.6.130, 6.12.78, 6.18.19 or 6.19.9 eliminates this vulnerability. Applying the patch a0fc1b9c738fba231f190ab960c83202722efee5/c59090c50f62a17129fc4c5407bc4071305a9e82/52db5ef163c96f916d424e472fb17aadc35a9f7a/b48a0f8d4541a4f6651dc9a64430ce9fdf5c120b/73a7a345816946d276ad2c46c8bb771de67cfc46/24a7b9daa103fa963b3fd37d8805b23e01621976/25dd70a03b1f5f3aa71e1a5091ecd9cd2a13ee43 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 vulnerability database at Tenable (315719). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.202
• 6.1.166
• 6.6.129
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
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• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
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• 6.12.24
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• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
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• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
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• 6.12.53
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• 6.12.55
• 6.12.56
• 6.12.57
• 6.12.58
• 6.12.59
• 6.12.60
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• 6.12.65
• 6.12.66
• 6.12.67
• 6.12.68
• 6.12.69
• 6.12.70
• 6.12.71
• 6.12.72
• 6.12.73
• 6.12.74
• 6.12.75
• 6.12.76
• 6.12.77
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3
• 6.19.4
• 6.19.5
• 6.19.6
• 6.19.7
• 6.19.8

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.5

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.1
NVD Vector: 🔒

CNA Base Score: 7.8
CNA Vector (Linux): 🔒

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: Buffer overflow
CWE: CWE-120 / CWE-119
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: 315719
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-43380

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.15.203/6.1.167/6.6.130/6.12.78/6.18.19/6.19.9
Patch: a0fc1b9c738fba231f190ab960c83202722efee5/c59090c50f62a17129fc4c5407bc4071305a9e82/52db5ef163c96f916d424e472fb17aadc35a9f7a/b48a0f8d4541a4f6651dc9a64430ce9fdf5c120b/73a7a345816946d276ad2c46c8bb771de67cfc46/24a7b9daa103fa963b3fd37d8805b23e01621976/25dd70a03b1f5f3aa71e1a5091ecd9cd2a13ee43

Timelineinfo

05/01/2026 CVE reserved
05/08/2026 +7 days Advisory disclosed
05/08/2026 +0 days VulDB entry created
05/22/2026 +13 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-43380 (🔒)
GCVE (CVE): GCVE-0-2026-43380
GCVE (VulDB): GCVE-100-362187

Entryinfo

Created: 05/08/2026 18:19
Updated: 05/22/2026 00:56
Changes: 05/08/2026 18:19 (59), 05/20/2026 06:17 (11), 05/21/2026 03:04 (10), 05/22/2026 00:56 (2)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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