Linux Kernel up to 6.19.5 dma_free_coherent buffer overflow

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 6.19.5. This impacts the function dma_free_coherent. This manipulation causes buffer overflow. This vulnerability is tracked as CVE-2026-43149. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.19.5. It has been declared as critical. Affected by this vulnerability is the function dma_free_coherent. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net: wan/fsl_ucc_hdlc: Fix dma_free_coherent() in uhdlc_memclean() The priv->rx_buffer and priv->tx_buffer are alloc'd together as contiguous buffers in uhdlc_init() but freed as two buffers in uhdlc_memclean(). Change the cleanup to only call dma_free_coherent() once on the whole buffer.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2026-43149 since 05/01/2026. The exploitation appears 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 $5k-$25k at the moment (estimation calculated on 05/18/2026).

Upgrading to version 5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.16 or 6.19.6 eliminates this vulnerability. Applying the patch 6496fb830cbb741d831225cc4e7e5601c6e42970/ba8d8429e5d6c36f9a654d2b96b9e043c43d92b4/011ae5dd84dc9f05eb9b8e1adff44252ac776e7b/0f85a9655445e67bb0238cfc983d7c383b54938e/84b932bc9899d43e5829e6cf088b72d73a922b2b/d8a522085d09b30aba1016daf1dddac37c0f0285/d68994e37ac3b285692559776e0279a88a3b5f8d/36bd7d5deef936c4e1e3cd341598140e5c14c1d3 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 CERT Bund (WID-SEC-2026-1405). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Debian Linux
• Oracle Linux
• Microsoft Azure Linux
• Open Source Linux Kernel

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.10.251
• 5.15.201
• 6.1.164
• 6.6.127
• 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
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 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
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.12.54
• 6.12.55
• 6.12.56
• 6.12.57
• 6.12.58
• 6.12.59
• 6.12.60
• 6.12.61
• 6.12.62
• 6.12.63
• 6.12.64
• 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
• 6.18.0
• 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
• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3
• 6.19.4
• 6.19.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

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Entryinfo

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