kernel: KVM: x86 emulator: limit instructions to 15 bytes
Published Nov 27, 2009
7.8
HIGHCVSS 2.0
EPSS 3.11%
Description
The do_insn_fetch function in arch/x86/kvm/emulate.c in the x86 emulator in the KVM subsystem in the Linux kernel before 2.6.32-rc8-next-20091125 tries to interpret instructions that contain too many bytes to be valid, which allows guest OS users to cause a denial of service (increased scheduling latency) on the host OS via unspecified manipulations related to SMP support.
Affected products
No data.
- < 2.6.32
- 2.6.32
- 2.6.32
- 2.6.32
- 2.6.32
- 2.6.32
- 2.6.32
- 2.6.32
- 2.6.32
No data.
Red Hat Enterprise Linux 5
kvm-0:83-105.el5_4.13
Fixed · RHSA-2009:1659
Red Hat Enterprise Virtualization for RHEL-5
rhev-hypervisor-0:5.4-2.1.3.el5_4rhev2_1
Fixed · RHSA-2009:1692
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | kvm-0:83-105.el5_4.13 | Fixed | RHSA-2009:1659 |
| Red Hat Enterprise Virtualization for RHEL-5 | rhev-hypervisor-0:5.4-2.1.3.el5_4rhev2_1 | Fixed | RHSA-2009:1692 |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:N/I:N/A:C
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (11 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 3.11% (0.03112) | 87.34th | v5 (v2026.06.15) |
| Jun 15, 2026 | 3.11% (0.03112) | 86.06th | v5 (v2026.06.15) |
| Mar 17, 2025 | 1.43% (0.01431) | 79.31th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.23% (0.00229) | 61.99th | v3 (v2023.03.01) |
| Jun 14, 2024 | 0.23% (0.00229) | 61.26th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.23% (0.00229) | 59.23th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Feb 13, 2023 | 1.54% (0.01537) | 74.00th | v2 (v2022.01.01) |
| Feb 3, 2023 | 2.69% (0.02686) | 82.44th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.54% (0.01537) | 72.41th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.54% (0.01537) | 51.33th | v2 (v2022.01.01) |
References (13)
- http://git.kernel.org/?p=linux/kernel/git/avi/kvm.git%3Ba=commit%3Bh=e42d9b8141d1f54ff72ad3850bb110c95a5f3b88 x_refsource_CONFIRM
- http://lists.opensuse.org/opensuse-security-announce/2010-03/msg00006.html vendor-advisoryx_refsource_SUSEThird Party Advisory
- http://secunia.com/advisories/37720 third-party-advisoryx_refsource_SECUNIAThird Party Advisory
- http://www.kernel.org/pub/linux/kernel/v2.6/next/patch-v2.6.32-rc8-next-20091125.gz x_refsource_CONFIRMPatchVendor Advisory
- http://www.openwall.com/lists/oss-security/2009/11/25/1 mailing-listx_refsource_MLISTMailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2009/11/25/3 mailing-listx_refsource_MLISTMailing ListThird Party Advisory
- http://www.securityfocus.com/bid/37130 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2009-4031 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=541160 x_refsource_CONFIRMIssue TrackingThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2009-4031
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11089 vdb-entrysignaturex_refsource_OVALThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2009-4031
- https://www.redhat.com/archives/fedora-package-announce/2009-December/msg00777.html vendor-advisoryx_refsource_FEDORAThird Party Advisory
Change history (0)
No recorded changes yet.