Medium (6.5). EPSS 0.5% chance of exploitation in the next 30 days.
The spectre_v2_select_mitigation function in arch/x86/kernel/cpu/bugs.c in the Linux kernel before 4.18.1 does not always fill RSB upon a context switch, which makes it easier for attackers to conduct userspace-userspace spectreRSB attacks.
Severity
CVSS 3.0
6.5 medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
EPSS
0.5% chance of exploitation in the next 30 days; higher than 43% of CVEs (scores of 2026-10-31)