Vulnerability in Linux
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.001 (2.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 2.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000
Affected products
- Linux — versions 2.6.12
References
Frequently asked questions
- What is CVE-2026-74663?
- CVE-2026-74663 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2026-08-22.
- How severe is CVE-2026-74663?
- High severity. CVSS v3 base score is 7.8 out of 10.