Kernel: KVM: debug exception via syscall emulation
Published Jul 30, 2018
7.8
HIGHCVSS 3.0
EPSS 0.67%
Description
A flaw was found in the Linux kernel before version 4.12 in the way the KVM module processed the trap flag(TF) bit in EFLAGS during emulation of the syscall instruction, which leads to a debug exception(#DB) being raised in the guest stack. A user/process inside a guest could use this flaw to potentially escalate their privileges inside the guest. Linux guests are not affected by this.
Affected products
- Vendor n/a Product Kernel: Defaultn/a
- Version 4.12StatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| n/a | Kernel: | n/a |
|
Configuration 1
- 7.0
- 7.0
- 7.0
- 7.4
- 7.4
- 7.5
- 7.0
Configuration 2
- 14.04
- 16.04
- 8.0
- 9.0
Configuration 3
- < 4.12
No data.
Red Hat Enterprise Linux 7
kernel-0:3.10.0-693.21.1.el7
Fixed · RHSA-2018:0395
Red Hat Enterprise Linux 7
kernel-rt-0:3.10.0-693.21.1.rt56.639.el7
Fixed · RHSA-2018:0412
Red Hat Enterprise Linux 5
kernel
Not affected
Red Hat Enterprise Linux 6
kernel
Not affected
Red Hat Enterprise Linux 7
kernel-alt
Not affected
Red Hat Enterprise MRG 2
realtime-kernel
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 7 | kernel-0:3.10.0-693.21.1.el7 | Fixed | RHSA-2018:0395 |
| Red Hat Enterprise Linux 7 | kernel-rt-0:3.10.0-693.21.1.rt56.639.el7 | Fixed | RHSA-2018:0412 |
| Red Hat Enterprise Linux 5 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 6 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-alt | Not affected | n/a |
| Red Hat Enterprise MRG 2 | realtime-kernel | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue does not affect the versions of the kernel package as shipped with Red Hat Enterprise Linux 5, 6 and Red Hat Enterprise MRG 2. This issue affects the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 7. Future kernel updates for Red Hat Enterprise Linux 7 may address this issue.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
AV:L/AC:L/Au:N/C:P/I:P/A:P
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
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (15 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.67% (0.00672) | 50.26th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.70% (0.00698) | 48.07th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.09% (0.00094) | 24.25th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.06% (0.00062) | 28.60th | v3 (v2023.03.01) |
| Jun 22, 2024 | 0.06% (0.00062) | 26.81th | v3 (v2023.03.01) |
| Jul 24, 2023 | 0.06% (0.00062) | 24.79th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.04% (0.00045) | 12.06th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.28% (0.01282) | 68.34th | v2 (v2022.01.01) |
| Feb 22, 2023 | 1.28% (0.01282) | 68.05th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.28% (0.01282) | 65.91th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.28% (0.01282) | 41.72th | v2 (v2022.01.01) |
| Feb 3, 2022 | 2.68% (0.02678) | 55.40th | v1 |
| Jan 6, 2022 | 2.68% (0.02678) | 54.96th | v1 |
| Sep 1, 2021 | 2.68% (0.02678) | 79.35th | v1 |
| Apr 14, 2021 | 2.68% (0.02678) | 0.00th | v1 |
References (16)
- http://www.openwall.com/lists/oss-security/2017/06/23/5 mailing-listx_refsource_MLISTMailing ListPatchThird Party Advisory
- http://www.securityfocus.com/bid/99263 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1038782 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://access.redhat.com/articles/3290921 x_refsource_CONFIRMPermissions RequiredThird Party Advisory
- https://access.redhat.com/errata/RHSA-2018:0395 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/errata/RHSA-2018:0412 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2017-7518 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1464473 Issue Tracking
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-7518 x_refsource_CONFIRMIssue TrackingPatchThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2017-7518
- https://usn.ubuntu.com/3619-1/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://usn.ubuntu.com/3619-2/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://usn.ubuntu.com/3754-1/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2017-7518
- https://www.debian.org/security/2017/dsa-3981 vendor-advisoryx_refsource_DEBIANThird Party Advisory
- https://www.spinics.net/lists/kvm/msg151817.html mailing-listx_refsource_MLISTMailing ListPatch
| Link | Providers | Tags |
|---|---|---|
| http://www.openwall.com/lists/oss-security/2017/06/23/5 | mailing-listx_refsource_MLISTMailing ListPatchThird Party Advisory | |
| http://www.securityfocus.com/bid/99263 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| http://www.securitytracker.com/id/1038782 | vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry | |
| https://access.redhat.com/articles/3290921 | x_refsource_CONFIRMPermissions RequiredThird Party Advisory | |
| https://access.redhat.com/errata/RHSA-2018:0395 | vendor-advisoryx_refsource_REDHATThird Party Advisory | |
| https://access.redhat.com/errata/RHSA-2018:0412 | vendor-advisoryx_refsource_REDHATThird Party Advisory | |
| https://access.redhat.com/security/cve/CVE-2017-7518 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1464473 | Issue Tracking | |
| https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-7518 | x_refsource_CONFIRMIssue TrackingPatchThird Party Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2017-7518 | ||
| https://usn.ubuntu.com/3619-1/ | vendor-advisoryx_refsource_UBUNTUThird Party Advisory | |
| https://usn.ubuntu.com/3619-2/ | vendor-advisoryx_refsource_UBUNTUThird Party Advisory | |
| https://usn.ubuntu.com/3754-1/ | vendor-advisoryx_refsource_UBUNTUThird Party Advisory | |
| https://www.cve.org/CVERecord?id=CVE-2017-7518 | ||
| https://www.debian.org/security/2017/dsa-3981 | vendor-advisoryx_refsource_DEBIANThird Party Advisory | |
| https://www.spinics.net/lists/kvm/msg151817.html | mailing-listx_refsource_MLISTMailing ListPatch |
Change history (0)
No recorded changes yet.