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Fencer Vulns
no cvss —

CVE-2023-54137 json

vfio/type1: fix cap_migration information leak

published 2025-12-24 10 mo ago modified 2026-06-17 4 mo ago also EUVD-2023-60308

cvss
—
not scored
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 11%
public exploits
0
none known

Summary

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

vfio/type1: fix cap_migration information leak

Fix an information leak where an uninitialized hole in struct vfio_iommu_type1_info_cap_migration on the stack is exposed to userspace.

The definition of struct vfio_iommu_type1_info_cap_migration contains a hole as shown in this pahole(1) output:

struct vfio_iommu_type1_info_cap_migration { struct vfio_info_cap_header header; /* 0 8 */ __u32 flags; /* 8 4 */

/* XXX 4 bytes hole, try to pack */

__u64 pgsize_bitmap; /* 16 8 */ __u64 max_dirty_bitmap_size; /* 24 8 */

/* size: 32, cachelines: 1, members: 4 */ /* sum members: 28, holes: 1, sum holes: 4 */ /* last cacheline: 32 bytes */ };

The cap_mig variable is filled in without initializing the hole:

static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu, struct vfio_info_cap *caps) { struct vfio_iommu_type1_info_cap_migration cap_mig;

cap_mig.header.id = VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION; cap_mig.header.version = 1;

cap_mig.flags = 0; /* support minimum pgsize */ cap_mig.pgsize_bitmap = (size_t)1 << __ffs(iommu->pgsize_bitmap); cap_mig.max_dirty_bitmap_size = DIRTY_BITMAP_SIZE_MAX;

return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig)); }

The structure is then copied to a temporary location on the heap. At this point it's already too late and ioctl(VFIO_IOMMU_GET_INFO) copies it to userspace later:

int vfio_info_add_capability(struct vfio_info_cap *caps, struct vfio_info_cap_header *cap, size_t size) { struct vfio_info_cap_header *header;

header = vfio_info_cap_add(caps, size, cap->id, cap->version); if (IS_ERR(header)) return PTR_ERR(header);

memcpy(header + 1, cap + 1, size - sizeof(*header));

return 0; }

This issue was found by code inspection.

Patch / fix

  • Linux Linux 5.10.195, 5.15.132, 6.1.53, 6.4.16, 6.5.3, 6.6
  • linux Debian 12 6.1.55-1
  • linux Debian 14, Debian 13 6.5.3-1

debian advisories DEBIAN-CVE-2023-54137

  • linux Ubuntu 22.04 LTS 5.15.0-94.104
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1053.58
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1051.59
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1050.55
  • linux-ibm Ubuntu 22.04 LTS 5.15.0-1046.49
  • linux-kvm Ubuntu 22.04 LTS 5.15.0-1050.55
  • linux-azure Ubuntu 22.04 LTS 5.15.0-1056.64
  • linux-gkeop Ubuntu 22.04 LTS 5.15.0-1036.42

ubuntu advisories UBUNTU-CVE-2023-54137

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 RHEL 9 5.14.0-427.13.1.el9_4
  • rv RHEL 9 5.14.0-427.13.1.el9_4
  • perf RHEL 9 5.14.0-427.13.1.el9_4
  • rtla RHEL 9 5.14.0-427.13.1.el9_4
  • bpftool RHEL 9 7.3.0-427.13.1.el9_4
  • libperf RHEL 9 5.14.0-427.13.1.el9_4
  • kernel-rt RHEL 9 5.14.0-427.13.1.el9_4
  • kernel-64k RHEL 9 5.14.0-427.13.1.el9_4

red hat advisories RHSA-2024:2394

  • kernel-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-40.1
  • kernel-source-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-40.1
  • kernel-source Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
  • kernel-default Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
  • kernel-kvmsmall Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
  • kernel-default-base Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1.21.16
  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.28.1
  • kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.28.1

suse advisories SUSE-SU-2026:20845-1SUSE-SU-2026:20876-1SUSE-SU-2026:20477-1SUSE-SU-2026:20498-1SUSE-SU-2026:0315-1SUSE-SU-2026:0293-1

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-2023-54137 updated cvss 5.5

kernel: Linux kernel: Information disclosure in VFIO Type1 module via uninitialized stack memory

  • Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-kvm, kernel-rt-core, kernel-rt-modules, kernel-rt-debug-kvm, kernel-rt-debug-core, +12 more
    affected: no fix available “Fix deferred”
  • Red Hat Enterprise Linux AppStream (v. 9) rv 5.14.0-427.13.1.el9_4, perf 5.14.0-427.13.1.el9_4, rtla 5.14.0-427.13.1.el9_4, kernel-devel-matched 5.14.0-427.13.1.el9_4, kernel-64k-devel-matched 5.14.0-427.13.1.el9_4, kernel-debug-devel-matched 5.14.0-427.13.1.el9_4, +6 more Red Hat Enterprise Linux BaseOS (v. 9) bpftool 7.3.0-427.13.1.el9_4, kernel 5.14.0-427.13.1.el9_4, kernel-64k 5.14.0-427.13.1.el9_4, kernel-core 5.14.0-427.13.1.el9_4, kernel-tools 5.14.0-427.13.1.el9_4, python3-perf 5.14.0-427.13.1.el9_4, +28 more Red Hat Enterprise Linux CRB (v. 9) libperf 5.14.0-427.13.1.el9_4, kernel-debuginfo-common-s390x 5.14.0-427.13.1.el9_4, kernel-debuginfo-common-x86_64 5.14.0-427.13.1.el9_4, kernel-debuginfo-common-aarch64 5.14.0-427.13.1.el9_4, kernel-debuginfo-common-ppc64le 5.14.0-427.13.1.el9_4 Red Hat Enterprise Linux NFV (v. 9) kernel-rt 5.14.0-427.13.1.el9_4, kernel-rt-kvm 5.14.0-427.13.1.el9_4, kernel-rt-core 5.14.0-427.13.1.el9_4, kernel-rt-modules 5.14.0-427.13.1.el9_4, kernel-rt-debug-kvm 5.14.0-427.13.1.el9_4, kernel-rt-debug-core 5.14.0-427.13.1.el9_4, +6 more Red Hat Enterprise Linux RT (v. 9) kernel-rt 5.14.0-427.13.1.el9_4, kernel-rt-core 5.14.0-427.13.1.el9_4, kernel-rt-modules 5.14.0-427.13.1.el9_4, kernel-rt-debug-core 5.14.0-427.13.1.el9_4, kernel-rt-modules-core 5.14.0-427.13.1.el9_4, kernel-rt-debug-modules 5.14.0-427.13.1.el9_4, +4 more
    fixed: vendor fix RHSA-2024:2394
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 10 kernel
    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

0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).

Affected products

  • Linux Linux

Classification

Technology feeds

References

Sources

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