PT-2024-11102 · Linux · Linux Kernel

Zenghui Yu · Published 2021-05-05 · Updated 2024-12-24 · CVE-2021-46997

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to 5.12.0-rc8+

Description The issue arises when booting a kernel with "irqchip.gicv3 pseudo nmi=1" on the command line, causing a warning during kernel entry due to the manipulation of the PMR. The lockdep hardirqs off() function checks if interrupts are masked before setting GIC PRIO PSR I SET in exception entry paths. To avoid this warning, GIC PRIO PSR I SET should be consistently set during exception entry. The local daif inherit() function needs to be updated to undo this, and local daif restore() will update both DAIF and the PMR.

Recommendations To resolve the issue, update the Linux kernel to a version that includes the fix for this vulnerability. Ensure that GIC PRIO PSR I SET is consistently set during exception entry, and update local daif inherit() to properly handle DAIF and PMR. If an update is not available, consider temporarily disabling the irqchip.gicv3 pseudo nmi=1 option to minimize the risk of exploitation.

Fix

RCE

Weakness Enumeration

CWE-20

Related Identifiers

BDU:2025-06531

CVE-2021-46997

Affected Products

Linux Kernel

References · 23

• https://git.kernel.org/stable/c/4d6a38da8e79e94cbd1344aa90876f0f805db705 · Patch
• https://cve.org/CVERecord?id=CVE-2021-46997 · Security Note
• https://osv.dev/vulnerability/CVE-2021-46997 · Vendor Advisory
• https://git.kernel.org/stable/c/51524fa8b5f7b879ba569227738375d283b79382 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-46997 · Vendor Advisory
• https://git.kernel.org/stable/c/d8d52005f57bbb4a4ec02f647e2555d327135c68 · Patch
• https://ubuntu.com/security/CVE-2021-46997 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2021-46997 · Vendor Advisory
• https://git.kernel.org/stable/c/e67a83f078005461b59b4c776e6b5addd11725fa · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2021-46997 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-46997 · Vendor Advisory
• https://bdu.fstec.ru/vul/2025-06531 · Security Note
• https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.5 · Note
• https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.38 · Note
• https://t.me/cvenotify/105395 · Telegram Post