Description
The x86 emulator in KVM 83, when a guest is configured for Symmetric Multiprocessing (SMP), does not properly restrict writing of segment selectors to segment registers, which might allow guest OS users to cause a denial of service (guest OS crash) or gain privileges on the guest OS by leveraging access to a (1) IO port or (2) MMIO region, and replacing an instruction in between emulator entry and instruction fetch.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 5.0 | kvm | 72+dfsg-5~lenny5 | DSA-2010-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | rhev-hypervisor +1 | 5.4-2.1.10.el5_4rhev2_1 | RHSA-2010:0172 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Rhel Virtualization 5 | kvm +3 | 83-105.el5_4.27 | RHSA-2010:0126 |
Advisories 3
- RHSA-2010:0172 Red Hat Security Advisory: rhev-hypervisor security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2010:0126 Red Hat Security Advisory: kvm security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- DSA-2010-1 kvm - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
References
- 38467 vdb-entry
- kernel-selectors-privilege-escalation(56662) vdb-entry
- RHSA-2010:0126 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=563463
- 1023663 vdb-entry
- oval:org.mitre.oval:def:10139 vdb-entry signature