CVE-2026-43097 [High] | Security Vulnerability in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: PCI: hv: Fix double ida_free in hv_pci_probe error path If hv_pci_probe() fails after storing the domain number in hbus->bridge->domain_nr, there is a call to free this domain_nr via pci_bus_release_emul_domain_nr(), however, during cleanup, the bridge release callback pci_release_host_bridge_dev() also frees the domain_nr causing ida_free to be called on same ID twice and triggering following warning: ida_free called for id=28971 which is not allocated. WARNING: lib/idr.c:594 at ida_free+0xdf/0x160, CPU#0: kworker/0:2/198 Call Trace: pci_bus_release_emul_domain_nr+0x17/0x20 pci_release_host_bridge_dev+0x4b/0x60 device_release+0x3b/0xa0 kobject_put+0x8e/0x220 devm_pci_alloc_host_bridge_release+0xe/0x20 devres_release_all+0x9a/0xd0 device_unbind_cleanup+0x12/0xa0 really_probe+0x1c5/0x3f0 vmbus_add_channel_work+0x135/0x1a0 Fix this by letting pci core handle the free domain_nr and remove the explicit free called in pci-hyperv driver.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-05-06	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-05-06

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.8	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	5.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.8

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

5.9

[email protected]

OS Trackers for CVE-2026-43097

vendor	priority	summary	link
`debian`	unimportant	CVE-2026-43097 unimportant 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-2026-43097
`redhat`	low	—	https://access.redhat.com/security/cve/CVE-2026-43097
`suse`	medium	CVE-2026-43097 severity moderate: SUSE including 21 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 198 product×package rows across 39 product lines (SUSE Linux Enterprise High Availability Extension 15 SP7, SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, … (39 product lines)): Known Not Affected 198.	https://www.suse.com/security/cve/CVE-2026-43097/
`ubuntu`	medium	CVE-2026-43097 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1047, ignored 169, not-affected 144, released 84, needs-triage 5.	https://ubuntu.com/security/CVE-2026-43097

Affected software / configurations for CVE-2026-43097

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 6.19, < 6.19.14	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	7.0	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
linux	linux_kernel	7.0	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
linux	linux_kernel	7.0	cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::
linux	linux_kernel	7.0	cpe:2.3:o:linux:linux_kernel:7.0:rc4::::::
linux	linux_kernel	7.0	cpe:2.3:o:linux:linux_kernel:7.0:rc5::::::
linux	linux_kernel	7.0	cpe:2.3:o:linux:linux_kernel:7.0:rc6::::::
linux	linux_kernel	7.0	cpe:2.3:o:linux:linux_kernel:7.0:rc7::::::

References for CVE-2026-43097

URL	Tags
https://git.kernel.org/stable/c/21bc8e0ba5c2a081b0a2808c976d4c9dbddf1e48	Patch
https://git.kernel.org/stable/c/b6422dff0e518245019233432b6bccfc30b73e2f	Patch

URL

CVE-2026-43097 | PCI: hv: Fix double ida_free in hv_pci_probe error path

Exploit prediction scoring system (EPSS) score for CVE-2026-43097

Common vulnerability scoring system (CVSS) metrics for CVE-2026-43097

Weakness enumeration for CVE-2026-43097

GitHub Security Advisory for CVE-2026-43097

OS Trackers for CVE-2026-43097

Affected software / configurations for CVE-2026-43097

References for CVE-2026-43097