PT-2026-39024 · Linux · Linux Kernel

Published 2026-05-08 · Updated 2026-05-08 · CVE-2026-43363

Positive Technologies (AI Summary)

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the x86 APIC implementation where firmware may re-enable x2apic mode during resume from s2ram (Suspend to RAM), even if the kernel disabled it during boot due to lack of IRQ remapping support or other reasons. This creates a mismatch where the kernel continues using the xapic interface while the hardware operates in x2apic mode, leading to system hangs. This occurs specifically on bare metal systems using defconfig and s2ram.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2026-43363

Affected Products

Linux Kernel

References · 10

• https://nvd.nist.gov/vuln/detail/CVE-2026-43363 · Security Note
• https://twitter.com/CVEnew/status/2052811007873974363 · Twitter Post
• https://git.kernel.org/stable/c/11712c4eb384098db4cb08792e223c818b908c1a · Note
• https://git.kernel.org/stable/c/f591938072115bf08730b8530c67fab189cc6308 · Note
• https://git.kernel.org/stable/c/1d8440c1e7c49715f937416ac90cf260f1f1712c · Note
• https://git.kernel.org/stable/c/1a85f84214f9d790216547ac6086bf8033cd9e5a · Note
• https://git.kernel.org/stable/c/965289b120cc68cca886c75219c68b8c15751d73 · Note
• https://git.kernel.org/stable/c/3dd0812a7c764cd8f3b0182441ac22da0a7f3b09 · Note
• https://git.kernel.org/stable/c/a6ad6f2e31b524cbb66b2f370bad0cf17d327e6c · Note
• https://git.kernel.org/stable/c/8cc7dd77a1466f0ec58c03478b2e735a5b289b96 · Note