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Fencer Vulns
medium 5.5

CVE-2026-23346 json

arm64: io: Extract user memory type in ioremap_prot()

published 2026-03-25 7 mo ago modified 2026-11-05 3 d ago also EUVD-2026-15313

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 2%
public exploits
0
none known

Summary

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

arm64: io: Extract user memory type in ioremap_prot()

The only caller of ioremap_prot() outside of the generic ioremap() implementation is generic_access_phys(), which passes a 'pgprot_t' value determined from the user mapping of the target 'pfn' being accessed by the kernel. On arm64, the 'pgprot_t' contains all of the non-address bits from the pte, including the permission controls, and so we end up returning a new user mapping from ioremap_prot() which faults when accessed from the kernel on systems with PAN:

| Unable to handle kernel read from unreadable memory at virtual address ffff80008ea89000 | ... | Call trace: | __memcpy_fromio+0x80/0xf8 | generic_access_phys+0x20c/0x2b8 | __access_remote_vm+0x46c/0x5b8 | access_remote_vm+0x18/0x30 | environ_read+0x238/0x3e8 | vfs_read+0xe4/0x2b0 | ksys_read+0xcc/0x178 | __arm64_sys_read+0x4c/0x68

Extract only the memory type from the user 'pgprot_t' in ioremap_prot() and assert that we're being passed a user mapping, to protect us against any changes in future that may require additional handling. To avoid falsely flagging users of ioremap(), provide our own ioremap() macro which simply wraps __ioremap_prot().

Patch / fix

  • Linux Linux 6.6.143, 6.12.93, 6.18.17, 6.19.7, 7.0
  • linux Debian 13 6.12.94-1
  • linux Debian 14 6.19.8-1

debian advisories DEBIAN-CVE-2026-23346

  • linux Ubuntu 24.04 LTS 6.8.0-146.146
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1066.69
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1070.78
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1065.73
  • linux-ibm Ubuntu 24.04 LTS 6.8.0-1066.67
  • linux-azure Ubuntu 24.04 LTS 6.8.0-1070.78
  • linux-gkeop Ubuntu 24.04 LTS 6.8.0-1051.55
  • linux-nvidia Ubuntu 24.04 LTS 6.8.0-1064.67

ubuntu advisories UBUNTU-CVE-2026-23346

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-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
  • kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.55.1
  • kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.55.1
  • kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
  • kernel-default SLE Workstation Extension 15 SP7, SLE Module for Legacy 15 SP7, SLE Module for Basesystem 15 SP7 +2 more 6.4.0-150700.53.55.1
  • kernel-zfcpdump SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
  • kernel-obs-build SLE Module for Development Tools 15 SP7 6.4.0-150700.53.55.1
  • kernel-default-base SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1.150700.17.33.1

suse advisories SUSE-SU-2026:2238-1SUSE-SU-2026:21834-1

  • kernel Azure Linux 3.0 6.6.143.1-1

azure linux advisories AZL-80627

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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-2026-23346 updated cvss 5.5

kernel: arm64: io: Extract user memory type in ioremap_prot()

  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +82 more Red Hat Enterprise Linux 10 kernel
    affected: no fix available “Fix deferred”
  • 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 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-selftests-internal
    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

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
3 d ago

Exploit prediction

0.13% chance of exploitation in the next 30 days, higher than 2% 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

Technology feeds

References

Sources

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