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 | Product | Affected | Fixed |
|---|---|---|---|
| [UNKNOWN] | Kernel: | 4.12 | — |
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 14 | linux | 4.11.11-1 | — |
| Debian 13 | linux | 4.11.11-1 | — |
| Debian 12 | linux | 4.11.11-1 | — |
| Debian 9 | linux | 4.9.30-2+deb9u5 | DSA-3981-1 |
| Debian 8 | linux | 3.16.43-2+deb8u5 | DSA-3981-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux-gcp-6.11 +4 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +2 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +3 | No fix yet | — |
| Ubuntu 16.04 LTS | linux | 4.4.0-119.143 | USN-3619-1 |
| Ubuntu 16.04 LTS | linux-aws | 4.4.0-1054.63 | USN-3619-1 |
| Ubuntu 16.04 LTS | linux-gcp | 4.13.0-1002.5 | — |
| Ubuntu 16.04 LTS | linux-hwe | 4.13.0-32.35~16.04.1 | — |
| Ubuntu 16.04 LTS | linux-kvm | 4.4.0-1020.25 | USN-3619-1 |
| Ubuntu 16.04 LTS | linux-raspi2 | 4.4.0-1086.94 | USN-3619-1 |
| Ubuntu 16.04 LTS | linux-snapdragon | 4.4.0-1088.93 | USN-3619-1 |
| Ubuntu 14.04 LTS | linux | 3.13.0-157.207 | USN-3754-1 |
| Ubuntu 14.04 LTS | linux-aws | 4.4.0-1016.16 | USN-3619-2 |
| Ubuntu 14.04 LTS | linux-lts-xenial | 4.4.0-119.143~14.04.1 | USN-3619-2 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro FIPS-updates 16.04 LTS | linux-fips | 4.4.0-1008.10 | — |
| Ubuntu Pro 20.04 LTS | linux-azure-fde-5.15 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | kernel-rt +10 | 3.10.0-693.21.1.rt56.639.el7 | RHSA-2018:0412 |
| RHEL 7 | perf +18 | 3.10.0-693.21.1.el7 | RHSA-2018:0395 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | kernel-docs | 4.4.90-92.45.3 | SUSE-SU-2017:2869-1 |
| SLES 12 SP2 | kernel-syms +3 | 4.4.90-92.45.1 | SUSE-SU-2017:2869-1 |
| SLES 12 SP1 | kernel-xen +3 | 3.12.74-60.64.63.1 | SUSE-SU-2017:2908-1 |
| SLES 12 SP1 | kgraft-patch-SLE12-SP1_Update_22 | 1-2.1 | SUSE-SU-2017:2908-1 |
| SLES 12 | kernel-ec2 +4 | 3.12.61-52.101.1 | SUSE-SU-2017:2920-1, SUSE-SU-2017:2908-1 |
| SLES 12 | kgraft-patch-SLE12_Update_28 | 1-8.1 | SUSE-SU-2017:2920-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP2 | kernel-syms +2 | 4.4.90-92.45.1 | SUSE-SU-2017:2869-1 |
| SLES for SAP 12 SP1 | kernel-xen +3 | 3.12.74-60.64.63.1 | SUSE-SU-2017:2908-1 |
| SLES for SAP 12 SP1 | kgraft-patch-SLE12-SP1_Update_22 | 1-2.1 | SUSE-SU-2017:2908-1 |
| SLE Real Time 12 SP2 | kernel-rt +3 | 4.4.88-18.1 | SUSE-SU-2017:2956-1 |
| SLE Live Patching 12 | kgraft-patch-SLE12-SP2_Update_14 | 1-2.4 | SUSE-SU-2017:2869-1 |
| SUSE OpenStack Cloud 6 | kernel-xen +3 | 3.12.74-60.64.63.1 | SUSE-SU-2017:2908-1 |
| SUSE OpenStack Cloud 6 | kgraft-patch-SLE12-SP1_Update_22 | 1-2.1 | SUSE-SU-2017:2908-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | kernel-uek +5 | 4.1.12-112.16.7.el7uek | ELSA-2018-4062 |
| Oracle Linux 7 | perf +11 | 3.10.0-693.21.1.el7 | ELSA-2018-0395 |
Advisories 12
- RHSA-2018:0412 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jul 1, 2026
- RHSA-2018:0395 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jul 1, 2026
- USN-3754-1 linux vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-3619-1 linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-3981-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-3619-2 linux-lts-xenial, linux-aws vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2017:2956-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:2908-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:2920-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:2869-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- ELSA-2018-4062 Important: Unbreakable Enterprise kernel security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Apr 10, 2018
- ELSA-2018-0395 Important: kernel security and bug fix update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Mar 7, 2018
References
- RHSA-2018:0412 vendor-advisory
- https://access.redhat.com/articles/3290921
- USN-3619-2 vendor-advisory
- RHSA-2018:0395 vendor-advisory
- USN-3754-1 vendor-advisory
- 1038782 vdb-entry
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-7518
- [oss-security] 20170623 CVE-2017-7518 Kernel: KVM: debug exception via syscall emulation mailing-list
- USN-3619-1 vendor-advisory
- DSA-3981 vendor-advisory
- [kvm] 20170622 [PATCH] KVM: x86: fix singlestepping over syscall mailing-list
- 99263 vdb-entry