What is CVE-2026-90255?

CVE-2026-90255 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10, affecting Linux kernel versions from 6.1 onward and patched in 6.1.188, 6.6.157, 6.12.110 and others. CVE-2026-90255 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-90255?

CVE-2026-90255 has a CVSS score of 8.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-90255?

Yes, CVE-2026-90255 has been patched. Fixed versions include 6.1.188, 6.6.157, 6.12.110 and others. If you are running Linux kernel 6.1 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-90255 actively exploited?

CVE-2026-90255 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-90255

High

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_conn: fix the SCO setup context lifetime hci_setup_sync() queues a conn_handle_t with a NULL destroy callback, so the context is only freed if hci_enhanced_setup_sync() actually runs. An entry that is cancelled instead is leaked, as _hci_cmd_sync_cancel_entry() does not release entry->data when there is no destroy callback, and hci_cmd_sync_clear() cancels every pending entry when the controller is unregistered. The context also stores a bare hci_conn pointer, so the connection can be freed while the work is queued. The dequeue in hci_conn_del() does not cover it either, as it matches on entry->data == conn and entry->data is the wrapper here. Same problem as commit 2f5d635ad590 ("Bluetooth: hci_sync: hold conn in hci_connect_acl/le_sync() callbacks"). Hold the connection and release both from a destroy callback. The submission failure path drops both, since hci_cmd_sync_submit() does not call the destroy callback when it fails to queue.

Package Linux Kernel

Published 2026-09-17

Last modified 2026-09-18

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

8.8

out of 10

High

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 6.1 and later are affected. Fixed in 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6, 7.3-rc1 and their respective stable series.

Affected from

≥ 6.1

Fixed in

✓ 6.1.188 6.1.x ✓ 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

6 total

Showing 5 of 6 references View all on NVD

Details

CVE ID CVE-2026-90255

Severity High

CVSS score 8.8 / 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-2026-90255?

CVE-2026-90255 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10 . It affects Linux kernel versions from 6.1 onward and has been patched in 6.1.188, 6.6.157, 6.12.110 and others. CVE-2026-90255 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-90255?

CVE-2026-90255 has a CVSS score of 8.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-90255?

Yes. CVE-2026-90255 has been patched. Fixed versions include 6.1.188, 6.6.157, 6.12.110 and others. If you are running Linux kernel 6.1 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-90255 actively exploited?

No. CVE-2026-90255 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.