CVE-2026-63955

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

Description A flaw exists in the mm/vmalloc component where the get vm area node() function incorrectly triggers a BUG() (a kernel panic) when bottom halves (BH) are disabled. This occurs because the in interrupt() function returns true both during actual interrupts and when BH are disabled. In the bridge code, calling rhashtable lookup insert fast() while BH are disabled leads to a chain of calls through kvmalloc() and vmalloc() that eventually triggers this failure, even if the system is not in a Non-Maskable Interrupt (NMI) or hard IRQ context.

Recommendations Replace the in interrupt() check with in nmi() || in hardirq() within the get vm area node() function.