CVE-2025-26403

Publication date 12 August 2025

Last updated 11 November 2025

Ubuntu priority

Cvss 3 Severity Score

Description

Out-of-bounds write in the memory subsystem for some Intel(R) Xeon(R) 6 processors when using Intel(R) SGX or Intel(R) TDX may allow a privileged user to potentially enable escalation of privilege via local access.

From the Ubuntu Security Team

Aviv Eisen and Avraham Shalev discovered that some Intel® Xeon® 6 processors when using Intel® SGX or Intel® TDX did not properly protect against out-of-bounds writes in the memory subsystem. A local authenticated user could potentially use this issue to escalate their privileges.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
intel-microcode	25.10 questing	Fixed 3.20250812.0ubuntu0.25.10.1
	25.04 plucky	Fixed 3.20250812.0ubuntu0.25.04.1
	24.04 LTS noble	Fixed 3.20250812.0ubuntu0.24.04.1
	22.04 LTS jammy	Fixed 3.20250812.0ubuntu0.22.04.1
	20.04 LTS focal	Fixed 3.20250812.0ubuntu0.20.04.1+esm1
	18.04 LTS bionic	Fixed 3.20250812.0ubuntu0.18.04.1+esm1
	16.04 LTS xenial	Fixed 3.20250812.0ubuntu0.16.04.1+esm1
	14.04 LTS trusty	Ignored see notes

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Notes

rodrigo-zaiden

trusty cannot use intel-microcode during early boot and is therefore generally not updated.

Severity score breakdown

Parameter	Value
Base score	7.2 · High
Attack vector	Local
Attack complexity	High
Privileges required	High
User interaction	None
Scope	Changed
Confidentiality	High
Integrity impact	High
Availability impact	None
Vector	CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:N

References

Related Ubuntu Security Notices (USN)

USN-7866-1
Intel Microcode vulnerabilities
10 November 2025