Linux Kernel up to 5.19.1 vt-d arch_test_bit array index

Summaryinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 5.4.210/5.10.136/5.15.60/5.18.17/5.19.1. This issue affects the function arch_test_bit of the component vt-d. This manipulation causes array index. This vulnerability is tracked as CVE-2022-50093. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.4.210/5.10.136/5.15.60/5.18.17/5.19.1. It has been declared as problematic. Affected by this vulnerability is the function arch_test_bit of the component vt-d. The manipulation with an unknown input leads to a array index vulnerability. The CWE definition for the vulnerability is CWE-129. The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: avoid invalid memory access via node_online(NUMA_NO_NODE) KASAN reports: [ 4.668325][ T0] BUG: KASAN: wild-memory-access in dmar_parse_one_rhsa (arch/x86/include/asm/bitops.h:214 arch/x86/include/asm/bitops.h:226 include/asm-generic/bitops/instrumented-non-atomic.h:142 include/linux/nodemask.h:415 drivers/iommu/intel/dmar.c:497) [ 4.676149][ T0] Read of size 8 at addr 1fffffff85115558 by task swapper/0/0 [ 4.683454][ T0] [ 4.685638][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc3-00004-g0e862838f290 #1 [ 4.694331][ T0] Hardware name: Supermicro SYS-5018D-FN4T/X10SDV-8C-TLN4F, BIOS 1.1 03/02/2016 [ 4.703196][ T0] Call Trace: [ 4.706334][ T0] <TASK> [ 4.709133][ T0] ? dmar_parse_one_rhsa (arch/x86/include/asm/bitops.h:214 arch/x86/include/asm/bitops.h:226 include/asm-generic/bitops/instrumented-non-atomic.h:142 include/linux/nodemask.h:415 drivers/iommu/intel/dmar.c:497) after converting the type of the first argument (@nr, bit number) of arch_test_bit() from `long` to `unsigned long`[0]. Under certain conditions (for example, when ACPI NUMA is disabled via command line), pxm_to_node() can return %NUMA_NO_NODE (-1). It is valid 'magic' number of NUMA node, but not valid bit number to use in bitops. node_online() eventually descends to test_bit() without checking for the input, assuming it's on caller side (which might be good for perf-critical tasks). There, -1 becomes %ULONG_MAX which leads to an insane array index when calculating bit position in memory. For now, add an explicit check for @node being not %NUMA_NO_NODE before calling test_bit(). The actual logics didn't change here at all. [0] https://github.com/norov/linux/commit/0e862838f290147ea9c16db852d8d494b552d38d

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2022-50093 since 06/18/2025. The exploitation appears to be difficult. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/16/2026).

The vulnerability scanner Nessus provides a plugin with the ID 287964 (EulerOS 2.0 SP10 : kernel (EulerOS-SA-2026-1101)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.211, 5.10.137, 5.15.61, 5.18.18 or 5.19.2 eliminates this vulnerability. Applying the patch b12304984654d8e58a2b22ff94c4410906d6267f/5659efdadf04b56707d58c1b758df16d2e0eff2c/0b4c0003aeda32a600f95df53b2848da8a5aa3fa/73ce2046e04ad488cecc66757c36cbe1bdf089d4/c2304c50f4d94f56c2e326f25c9dc8cf2ba6f5fa/b0b0b77ea611e3088e9523e60860f4f41b62b235 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (287964) and CERT Bund (WID-SEC-2025-1350). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Dell Avamar
• Dell NetWorker
• Dell Secure Connect Gateway
• IBM QRadar SIEM

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.4.210
• 5.10.136
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.15.49
• 5.15.50
• 5.15.51
• 5.15.52
• 5.15.53
• 5.15.54
• 5.15.55
• 5.15.56
• 5.15.57
• 5.15.58
• 5.15.59
• 5.15.60
• 5.18.0
• 5.18.1
• 5.18.2
• 5.18.3
• 5.18.4
• 5.18.5
• 5.18.6
• 5.18.7
• 5.18.8
• 5.18.9
• 5.18.10
• 5.18.11
• 5.18.12
• 5.18.13
• 5.18.14
• 5.18.15
• 5.18.16
• 5.18.17
• 5.19.0
• 5.19.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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Entryinfo

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