VOMIT (go/vomit) has received an external vulnerability report for the Linux kernel.
Advisory: CVE-2018-1087
Details: http://vomit.googleplex.com/advisory?id=CVE/CVE-2018-1087
CVSS severity score: 4.6/10.0
Description:
kernel KVM before versions kernel 4.16, kernel 4.16-rc7, kernel 4.17-rc1, kernel 4.17-rc2 and kernel 4.17-rc3 is vulnerable to a flaw in the way the Linux kernel's KVM hypervisor handled exceptions delivered after a stack switch operation via Mov SS or Pop SS instructions. During the stack switch operation, the processor did not deliver interrupts and exceptions, rather they are delivered once the first instruction after the stack switch is executed. An unprivileged KVM guest user could use this flaw to crash the guest or, potentially, escalate their privileges in the guest.
This bug was filed by http://go/vomit
Please contact us at vomit-team@google.com if you need any assistance.
Comment 1 by zsm@chromium.org
, Jun 20 2018Labels: Security_Impact-Stable Security_Severity-Low Pri-3
Owner: zsm@chromium.org
Status: WontFix (was: Untriaged)
The upstream commit is 32d43cd391ba ("kvm/x86: fix icebp instruction handling"). This commit is present in 4.14, 4.4, 3,18. Older kernels do not have this commit. Applying the patch causes merge conflicts, upstream stable kernels for <= 3.14 do not have this commit. Given the severity, marking as WontFix.