Vulnerability in Linux

CVE-2026-23437

In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect late read accesses to the hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. This is not proper, a conversion from a ref to a locked netdev must include a liveness check (a check if the netdev hasn't been unregistered already). Fix the read cases (those under RCU). Writes needs a separate change to protect from creating the hierarchy after flush has already run.

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 (2.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 2.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-23437: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000

Affected products

  • Linux — versions 4b623f9f0f59652ea71fcb27d60b4c3b65126dbb, 6.13, 0
  • Linux Kernel — versions 6.13, 7.0

References

Frequently asked questions

What is CVE-2026-23437?
CVE-2026-23437 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2026-04-03.
How severe is CVE-2026-23437?
High severity. CVSS v3 base score is 7.8 out of 10.