What is CVE-2026-99017?

CVE-2026-99017 is a High severity Linux kernel vulnerability with a CVSS score of 7.0 out of 10, affecting Linux kernel versions from 6.14 onward and patched in 6.18.57, 7.2.11 and 7.3. CVE-2026-99017 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-99017?

CVE-2026-99017 has a CVSS score of 7.0 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-99017?

Yes, CVE-2026-99017 has been patched. Fixed versions include 6.18.57, 7.2.11 and 7.3. If you are running Linux kernel 6.14 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-99017 actively exploited?

CVE-2026-99017 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-99017

High

In the Linux kernel, the following vulnerability has been resolved: riscv: errata: select RISCV_ALTERNATIVE_EARLY for THEAD GHOSTWRITE errata_probe_ghostwrite() only marks the CPU as vulnerable when it is called at the RISCV_ALTERNATIVES_EARLY_BOOT stage, and the mitigation in ghostwrite_enable_mitigation() only takes effect if the vulnerable state was recorded before the boot alternatives are patched. The early boot stage is only executed when CONFIG_RISCV_ALTERNATIVE_EARLY is enabled, which currently is only selected by ERRATA_THEAD_MAE. In a kernel built with ERRATA_THEAD_GHOSTWRITE=y but ERRATA_THEAD_MAE=n, the early alternatives never run, so ghostwrite_state is never set to VULNERABLE: ghostwrite_enable_mitigation() returns false, xtheadvector remains enabled, and sysfs reports "Not affected" on a vulnerable T-Head C9xx CPU. Select RISCV_ALTERNATIVE_EARLY from ERRATA_THEAD_GHOSTWRITE so that the vulnerability is detected in the early boot stage and the default mitigation is applied.

Package Linux Kernel

Published 2026-10-23

Last modified 2026-10-24

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.0

out of 10

High

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected versions

Linux kernel versions 6.14 and later are affected. Fixed in 6.18.57, 7.2.11, 7.3 and their respective stable series.

Affected from

≥ 6.14

Fixed in

✓ 6.18.57 6.18.x ✓ 7.2.11 7.2.x ✓ 7.3

References

3 total

Details

CVE ID CVE-2026-99017

Severity High

CVSS score 7.0 / 10

CVSS version 3.1

Published 2026-10-23

Modified 2026-10-24

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-99017?

CVE-2026-99017 is a High severity Linux kernel vulnerability with a CVSS score of 7.0 out of 10 . It affects Linux kernel versions from 6.14 onward and has been patched in 6.18.57, 7.2.11 and 7.3. CVE-2026-99017 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-99017?

CVE-2026-99017 has a CVSS score of 7.0 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-99017?

Yes. CVE-2026-99017 has been patched. Fixed versions include 6.18.57, 7.2.11 and 7.3. If you are running Linux kernel 6.14 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-99017 actively exploited?

No. CVE-2026-99017 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.