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Fencer Vulns
medium 5.5

CVE-2026-64254 json

NTB: epf: Avoid pci_iounmap() with offset when PEER_SPAD and CONFIG share BAR

published 2026-07-24 3 mo ago modified 2026-11-08 21 h ago also EUVD-2026-48663

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 1%
public exploits
0
none known

Summary

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

NTB: epf: Avoid pci_iounmap() with offset when PEER_SPAD and CONFIG share BAR

When BAR_PEER_SPAD and BAR_CONFIG share one PCI BAR, the module teardown path ends up calling pci_iounmap() on the same iomem with some offset, which is unnecessary and triggers a kernel warning like the following:

Trying to vunmap() nonexistent vm area (0000000069a5ffe8) WARNING: mm/vmalloc.c:3470 at vunmap+0x58/0x68, CPU#5: modprobe/2937 [...] Call trace: vunmap+0x58/0x68 (P) iounmap+0x34/0x48 pci_iounmap+0x2c/0x40 ntb_epf_pci_remove+0x44/0x80 [ntb_hw_epf] pci_device_remove+0x48/0xf8 device_remove+0x50/0x88 device_release_driver_internal+0x1c8/0x228 driver_detach+0x50/0xb0 bus_remove_driver+0x74/0x100 driver_unregister+0x34/0x68 pci_unregister_driver+0x34/0xa0 ntb_epf_pci_driver_exit+0x14/0xfe0 [ntb_hw_epf] [...]

Fix it by unmapping only when PEER_SPAD and CONFIG use difference bars.

Patch / fix

  • Linux Linux 6.1.177, 6.6.144, 6.12.95, 6.18.38, 7.1.3, 7.2
  • linux Debian 12 6.1.177-1
  • linux Debian 13 6.12.95-1
  • linux Debian 14 7.1.3-1

debian advisories DEBIAN-CVE-2026-64254

  • linux Ubuntu 24.04 LTS 6.8.0-147.147
  • linux Ubuntu 26.04 LTS 7.0.0-31.31
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1067.70
  • linux-aws Ubuntu 26.04 LTS 7.0.0-1012.12
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1071.79
  • linux-gcp Ubuntu 26.04 LTS 7.0.0-1011.11
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1066.74
  • linux-gke Ubuntu 26.04 LTS 7.0.0-1006.7

ubuntu advisories UBUNTU-CVE-2026-64254

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-source openSUSE Tumbleweed 7.1.7-1.1

opensuse advisories openSUSE-SU-2026:11476-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-64254 updated cvss 5.5

kernel: NTB: epf: Avoid pci_iounmap() with offset when PEER_SPAD and CONFIG share BAR

  • Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
    affected: no fix available “Fix deferred”
  • Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8
    under investigation
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +2 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +9 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +30 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +84 more Red Hat Enterprise Linux 10 kernel 6.12.0-250.el10
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.11% chance of exploitation in the next 30 days, higher than 1% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Linux Linux

Classification

Weakness
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.