CVE-2026-43383

In the Linux kernel, the following vulnerability has been resolved: net/tcp-md5: Fix MAC comparison to be constant-time To prevent timing attacks, MACs need to be compared in constant time. Use the appropriate helper function for this.

CVSS v3 9.4 CRITICAL

9.4^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/02669e2a4d207068edce7e8b5fafd85822018ce6	Patch
https://git.kernel.org/stable/c/345a9530756528d7ca407663d659c3c40e75c3dd	Patch
https://git.kernel.org/stable/c/46d0d6f50dab706637f4c18a470aac20a21900d3	Patch
https://git.kernel.org/stable/c/5d305a95130a8d08b9545e47f1e18d29d59866cb	Patch
https://git.kernel.org/stable/c/821c8751fdeecdeecabeb11704dd33439c9e4bbc	Patch
https://git.kernel.org/stable/c/ae3831b44f477de048287493e184fc3ff913b624	Patch
https://git.kernel.org/stable/c/b502e97e29d791ff7a8051f29a414535739be218	Patch
https://git.kernel.org/stable/c/ff44ec94d4fc8348600a69de0a8fa1102c23bce8

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::

History

11 Nov 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: net/tcp-md5: Corrección de la comparación de MAC para que sea de tiempo constante Para prevenir ataques de temporización, las MAC deben compararse en tiempo constante. Utilice la función auxiliar adecuada para esto.

19 Oct 2026, 20:18

Type	Values Removed	Values Added
CWE		CWE-208

Information

Published : 2026-05-08 15:16

Updated : 2026-11-11 20:10

NVD link : CVE-2026-43383

Mitre link : CVE-2026-43383

CVE.ORG link : CVE-2026-43383

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo CWE-208

Observable Timing Discrepancy

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