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.
4.13.0-16.194.13.0-17.204.13.0-25.294.13.0-32.354.15.0-10.114.15.0-12.134.15.0-13.144.15.0-15.164.15.0-19.204.15.0-20.21+8 more4.15.0-36.393.11.0-12.194.2.0-16.194.2.0-17.214.2.0-19.234.3.0-1.104.3.0-2.114.3.0-5.164.3.0-6.174.3.0-7.184.4.0-10.254.4.0-101.124+71 more4.4.0-137.1634.4.0-1002.24.4.0-1003.34.4.0-1005.54.4.0-1006.64.4.0-1009.94.4.0-1010.104.4.0-1011.114.4.0-1012.124.4.0-1014.144.4.0-1016.16+9 more4.4.0-1031.344.4.0-1001.104.4.0-1003.124.4.0-1004.134.4.0-1007.164.4.0-1009.184.4.0-1011.204.4.0-1012.214.4.0-1013.224.4.0-1016.254.4.0-1017.26+30 more4.4.0-1069.794.15.0-1001.14.15.0-1003.34.15.0-1005.54.15.0-1006.64.15.0-1007.74.15.0-1009.94.15.0-1010.104.15.0-1011.114.15.0-1016.164.15.0-1017.17+3 more4.15.0-1023.234.15.0-1030.31~16.04.14.15.0-1023.24~14.04.14.15.0-1030.31~14.04.14.11.0-1009.94.11.0-1011.114.11.0-1013.134.11.0-1014.144.11.0-1015.154.11.0-1016.164.13.0-1005.74.13.0-1006.84.13.0-1007.94.13.0-1009.12+12 more4.15.0-1025.26~16.04.14.15.0-1002.24.15.0-1003.34.15.0-1004.44.15.0-1008.84.15.0-1009.94.15.0-1012.124.15.0-1013.134.15.0-1014.144.15.0-1018.184.15.0-1019.19+3 more4.15.0-1025.26Exploitability
AV:LAC:LPR:LUI:NScope
S:CImpact
C:HI:NA:NCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N