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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.13%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.13% probability · 3th percentile
- CISA KEV
- Not listed
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.