Out-of-bounds Write Affecting openshift/ose-rhel-coreos-9 package, versions *


Severity

Recommended
0.0
medium
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.19% (9th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-RHEL8-OPENSHIFTOSERHELCOREOS9-22344015
  • published8 Nov 2026
  • disclosed3 Nov 2026

Introduced: 3 Nov 2026

NewCVE-2026-99258  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:8 openshift/ose-rhel-coreos-9.

NVD Description

Note: Versions mentioned in the description apply only to the upstream openshift/ose-rhel-coreos-9 package and not the openshift/ose-rhel-coreos-9 package as distributed by RHEL. See How to fix? for RHEL:8 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

x86/hyperv: Avoid using per-cpu output page in hv_apicid_to_vp_index()

hv_apicid_to_vp_index() currently uses the per-cpu hypercall input and output pages. This function is called when running in VTL2 and when running in an SEV-SNP CoCo VM with no paravisor. In the former case, the output page is allocated, but in the latter case it is not, so the hypervisor stores the output VP index in memory that has not been allocated by the guest.

Fix this by using the input page for both input and output. The hypercall has very small input and output, so sharing the same page for both is straightforward. An alternative fix is to allocate the per-cpu output page when running in an SEV-SNP CoCo guest, but this uses significantly more memory, particularly with larger vCPUs counts.

CVSS Base Scores

version 3.1