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- CVEs with nessus.description==This update for kvm fixes the following issues: This update has the
next round of Spectre v2 related patches, which now integrates with
corresponding changes in libvirt. A January 2018 release of qemu
initially addressed the Spectre v2 vulnerability for KVM guests by
exposing the spec-ctrl feature for all x86 vcpu types, which was the
quick and dirty approach, but not the proper solution. We remove that
initial patch and now rely on patches from upstream. This update
defines spec_ctrl and ibpb cpu feature flags as well as new cpu models
which are clones of existing models with either -IBRS or -IBPB added
to the end of the model name. These new vcpu models explicitly include
the new feature(s), whereas the feature flags can be added to the cpu
parameter as with other features. In short, for continued Spectre v2
protection, ensure that either the appropriate cpu feature flag is
added to the QEMU command-line, or one of the new cpu models is used.
Although migration from older versions is supported, the new cpu
features won't be properly exposed to the guest until it is restarted
with the cpu features explicitly added. A reboot is insufficient. A
warning patch is added which attempts to detect a migration from a
qemu version which had the quick and dirty fix (it only detects
certain cases, but hopefully is helpful.) For additional information
on Spectre v2 as it relates to QEMU, see:
https://www.qemu.org/2018/02/14/qemu-2-11-1-and-spectre-update/
(CVE-2017-5715 bsc#1068032) A patch is added to continue to detect
Spectre v2 mitigation features (as shown by cpuid), and if found
provide that feature to guests, even if running on older KVM (kernel)
versions which do not yet expose that feature to QEMU. (bsc#1082276)
Additional security fixes :
- CVE-2018-5683: An out-of-bounds read in vga_draw_text
routine was fixed which could lead to crashes or
information leakage. (bsc#1076114)
- CVE-2018-7550: multiboot OOB access while loading kernel
image was fixed that could lead to crashes (bsc#1083291)
- CVE-2017-18030: An out-of-bounds access in
cirrus_invalidate_region routine could lead to crashes
or information leakage (bsc#1076179)
- Eliminate bogus use of CPUID_7_0_EDX_PRED_CMD which
we've carried since the initial Spectre v2 patch was
added. EDX bit 27 of CPUID Leaf 07H, Sub-leaf 0 provides
status on STIBP, and not the PRED_CMD MSR. Exposing the
STIBP CPUID feature bit to the guest is wrong in
general, since the VM doesn't directly control the
scheduling of physical hyperthreads. This is left
strictly to the L0 hypervisor.
Note that Tenable Network Security has extracted the preceding
description block directly from the SUSE security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues.
Max CVSS | 0 |
Min CVSS | 0 |
Total Count | 2 |
| ID | CVSS | Summary | Last (major) update | Published |
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