CVE-2022-50093 [High] | Out-of-bounds Read in Linux Kernel

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

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-06-18	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-06-18

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.1	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	5.2	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.1

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

5.2

[email protected]

OS Trackers for CVE-2022-50093

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2022-50093 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2022-50093
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2022-50093
`suse`	medium	—	https://www.suse.com/security/cve/CVE-2022-50093/
`ubuntu`	medium	CVE-2022-50093 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, ignored 151, released 135, not-affected 100, needed 19, needs-triage 1.	https://ubuntu.com/security/CVE-2022-50093

Affected software / configurations for CVE-2022-50093

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 2.6.33, < 5.4.211	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.5, < 5.10.137	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.11, < 5.15.61	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.16, < 5.18.18	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.19, < 5.19.2	cpe:2.3:o:linux:linux_kernel::::::::

References for CVE-2022-50093

URL	Tags
https://git.kernel.org/stable/c/0b4c0003aeda32a600f95df53b2848da8a5aa3fa	Patch
https://git.kernel.org/stable/c/5659efdadf04b56707d58c1b758df16d2e0eff2c	Patch
https://git.kernel.org/stable/c/73ce2046e04ad488cecc66757c36cbe1bdf089d4	Patch
https://git.kernel.org/stable/c/b0b0b77ea611e3088e9523e60860f4f41b62b235	Patch
https://git.kernel.org/stable/c/b12304984654d8e58a2b22ff94c4410906d6267f	Patch
https://git.kernel.org/stable/c/c2304c50f4d94f56c2e326f25c9dc8cf2ba6f5fa	Patch

URL

CVE-2022-50093 | iommu/vt-d: avoid invalid memory access via node_online(NUMA_NO_NODE)

Exploit prediction scoring system (EPSS) score for CVE-2022-50093

Common vulnerability scoring system (CVSS) metrics for CVE-2022-50093

Weakness enumeration for CVE-2022-50093

OS Trackers for CVE-2022-50093

Affected software / configurations for CVE-2022-50093

References for CVE-2022-50093