CVE-2026-74663

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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/08dc49df1527b09d9ea225a7265bbf6c237097bf
https://git.kernel.org/stable/c/2759acf08a3454866660edcd3ef4e64139f254a6
https://git.kernel.org/stable/c/8ca8cdb74939581339e1ae370193c0adb5a85336
https://git.kernel.org/stable/c/9f69bb9fdaa2fe64b68bb62fb84d405784bee540
https://git.kernel.org/stable/c/a4b14a4df29d36458a943f9b521ddd0f940363cc
https://git.kernel.org/stable/c/a627d36c2a94e18c8c105ae68008786dfd85592e
https://git.kernel.org/stable/c/dedd34b0f2310e28c5f6d4875cfbf4b7ed821c01
https://git.kernel.org/stable/c/e2d658c6427844cee5bc654b436ca68d680b6148

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-22 16:16

Updated : 2026-08-27 13:18

NVD link : CVE-2026-74663

Mitre link : CVE-2026-74663

CVE.ORG link : CVE-2026-74663

JSON object : View

Products Affected

No product.

CWE

No CWE.

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The existing loop check does not\ncover the create-and-graft path, so a hierarchy can still be extended by\ncreating a new child qdisc below an already deep parent.\n\nStore the hierarchy depth in struct Qdisc and update it when qdiscs are\ngrafted. Reject new child qdiscs once the parent is already at the maximum\nallowed depth."}], "lastModified": "2026-08-27T13:18:36.473", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}