What is CVE-2026-90153?

CVE-2026-90153 is a High severity Linux kernel vulnerability with a CVSS score of 8.1 out of 10, affecting Linux kernel versions from 5.15.62 onward and patched in 6.6.157, 6.12.110, 6.18.52 and others. CVE-2026-90153 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-90153?

CVE-2026-90153 has a CVSS score of 8.1 out of 10, rated High severity. The vector string is CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

Is there a patch available for CVE-2026-90153?

Yes, CVE-2026-90153 has been patched. Fixed versions include 6.6.157, 6.12.110, 6.18.52 and others. If you are running Linux kernel 5.15.62 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-90153 actively exploited?

CVE-2026-90153 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-90153

High

In the Linux kernel, the following vulnerability has been resolved: ksmbd: bound smb_check_perm_dacl() ACE walks by DACL size smb_check_perm_dacl() validates that the DACL fits inside the NT security descriptor, but then bounds its two ACE walks by the remaining NTSD length (acl_size) rather than the DACL's declared size (pdacl_size). When pdacl->size is smaller than the trailing NTSD buffer, bytes after the declared DACL boundary - still inside the stored security descriptor - are parsed as ACEs during access checks. A crafted DACL can place an access-granting ACE beyond pdacl->size, and the current code accepts it during SMB2_CREATE access validation, while parse_dacl() and smb_inherit_dacl() stop at pdacl_size. Bound both ACE walks by pdacl_size to match the DACL boundary semantics used elsewhere in the server. Validation: - semantic KUnit harness shows the post-boundary ACE is selected before the fix and rejected (EACCES) after it - linux master (7.2-rc6), x86_64

Package Linux Kernel

Published 2026-09-17

Last modified 2026-09-18

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

8.1

out of 10

High

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Vector string

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

Affected versions

Linux kernel versions 5.15.62, 5.18.18, 5.19.2, 6.0 and later are affected. Fixed in 6.6.157, 6.12.110, 6.18.52, 7.2.6, 7.3-rc1 and their respective stable series.

Affected from

≥ 5.15.62 ≥ 5.18.18 ≥ 5.19.2 ≥ 6.0

Fixed in

✓ 6.6.157 6.6.x ✓ 6.12.110 6.12.x ✓ 6.18.52 6.18.x ✓ 7.2.6 7.2.x ✓ 7.3-rc1

References

5 total

Details

CVE ID CVE-2026-90153

Severity High

CVSS score 8.1 / 10

CVSS version 3.1

Published 2026-09-17

Modified 2026-09-18

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-90153?

CVE-2026-90153 is a High severity Linux kernel vulnerability with a CVSS score of 8.1 out of 10 . It affects Linux kernel versions from 5.15.62 onward and has been patched in 6.6.157, 6.12.110, 6.18.52 and others. CVE-2026-90153 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-90153?

CVE-2026-90153 has a CVSS score of 8.1 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.
Is there a patch available for CVE-2026-90153?

Yes. CVE-2026-90153 has been patched. Fixed versions include 6.6.157, 6.12.110, 6.18.52 and others. If you are running Linux kernel 5.15.62 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-90153 actively exploited?

No. CVE-2026-90153 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.