Out-of-bounds Read in Linux

CVE-2026-43274

In the Linux kernel, the following vulnerability has been resolved: mailbox: mchp-ipc-sbi: fix out-of-bounds access in mchp_ipc_get_cluster_aggr_irq() The cluster_cfg array is dynamically allocated to hold per-CPU configuration structures, with its size based on the number of online CPUs. Previously, this array was indexed using hartid, which may be non-contiguous or exceed the bounds of the array, leading to out-of-bounds access. Switch to using cpuid as the index, as it is guaranteed to be within the valid range provided by for_each_online_cpu().

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.4 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.002 (8.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 8.1% 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-2026-43274: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.001

Affected products

  • Linux — versions e4b1d67e71419c4af581890ecea84b04920d4116, 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, 7.0
  • Linux Kernel

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-43274?
CVE-2026-43274 is a high-severity vulnerability in Linux, classified under Out-of-bounds Read. CVSS score: 8.4/10. Published 2026-05-06.
How severe is CVE-2026-43274?
High severity. CVSS v3 base score is 8.4 out of 10.