What is CVE-2026-74663?

CVE-2026-74663 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 2.6.12 onward and patched in 5.10.267, 5.15.218, 6.1.183 and others. CVE-2026-74663 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-74663?

CVE-2026-74663 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-74663?

Yes, CVE-2026-74663 has been patched. Fixed versions include 5.10.267, 5.15.218, 6.1.183 and others. If you are running Linux kernel 2.6.12 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-74663 actively exploited?

CVE-2026-74663 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-74663

High

In the Linux kernel, the following vulnerability has been resolved: net/sched: reject overly deep qdisc hierarchies Deep qdisc hierarchies can lead to excessive recursion in qdisc tree walkers and exhaust the kernel stack. The existing loop check does not cover the create-and-graft path, so a hierarchy can still be extended by creating a new child qdisc below an already deep parent. Store the hierarchy depth in struct Qdisc and update it when qdiscs are grafted. Reject new child qdiscs once the parent is already at the maximum allowed depth.

Package Linux Kernel

Published 2026-08-22

Last modified 2026-08-27

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 2.6.12 and later are affected. Fixed in 5.10.267, 5.15.218, 6.1.183, 6.6.152, 6.12.104, 6.18.45, 7.1.9, 7.2 and their respective stable series.

Affected from

≥ 2.6.12

Fixed in

✓ 5.10.267 5.10.x ✓ 5.15.218 5.15.x ✓ 6.1.183 6.1.x ✓ 6.6.152 6.6.x ✓ 6.12.104 6.12.x ✓ 6.18.45 6.18.x ✓ 7.1.9 7.1.x ✓ 7.2

References

8 total

Showing 5 of 8 references View all on NVD

Details

CVE ID CVE-2026-74663

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-08-22

Modified 2026-08-27

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-74663?

CVE-2026-74663 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 2.6.12 onward and has been patched in 5.10.267, 5.15.218, 6.1.183 and others. CVE-2026-74663 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-74663?

CVE-2026-74663 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-74663?

Yes. CVE-2026-74663 has been patched. Fixed versions include 5.10.267, 5.15.218, 6.1.183 and others. If you are running Linux kernel 2.6.12 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-74663 actively exploited?

No. CVE-2026-74663 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.