--- title: "CVE-2018-3646\n | Ubuntu" description: Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things. url: https://ubuntu.com/security/CVE-2018-3646?format=md keywords: index, follow --- # CVE-2018-3646 Publication date 14 August 2018 Last updated 4 July 2026 --- Ubuntu priority **High** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) ## Cvss 3 Severity Score **5.6 · Medium** [Score breakdown](https://ubuntu.com/security/CVE-2018-3646?format=md#impact-score) Toggle side navigation ## Description Systems with microprocessors utilizing speculative execution and address translations may allow unauthorized disclosure of information residing in the L1 data cache to an attacker with local user access with guest OS privilege via a terminal page fault and a side-channel analysis. ### From the Ubuntu Security Team It was discovered that memory present in the L1 data cache of an Intel CPU core may be exposed to a malicious process that is executing on the CPU core. This vulnerability is also known as L1 Terminal Fault (L1TF). A local attacker in a guest virtual machine could use this to expose sensitive information (memory from other guests or the host OS). [Read the notes from the security team](https://ubuntu.com/security/CVE-2018-3646?format=md#notes) ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | linux-aws-fips | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy FIPS Updates | Not affected | | 20.04 LTS focal FIPS | Not affected | | 18.04 LTS bionic FIPS | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-azure-fips | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy FIPS Updates | Not affected | | 20.04 LTS focal FIPS | Not affected | | 18.04 LTS bionic FIPS | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-gcp-fips | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy FIPS Updates | Not affected | | 20.04 LTS focal FIPS | Not affected | | 18.04 LTS bionic FIPS | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | intel-microcode | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Fixed 3.20180807a.0ubuntu0.18.04.1 | | 16.04 LTS xenial | Fixed 3.20180807a.0ubuntu0.16.04.1 | | 14.04 LTS trusty | Fixed 3.20180807a.0ubuntu0.14.04.1 | | linux | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Fixed 4.15.0-32.35 | | 16.04 LTS xenial | Fixed 4.4.0-133.159 | | 14.04 LTS trusty | Fixed 3.13.0-155.205 | | linux-aws | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Fixed 4.15.0-1019.19 | | 16.04 LTS xenial | Fixed 4.4.0-1065.75 | | 14.04 LTS trusty | Fixed 4.4.0-1027.30 | | linux-aws-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-aws-5.4 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-aws-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-aws-hwe | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not affected | | 14.04 LTS trusty | Not in release | | linux-azure | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Fixed 4.15.0-1021.21 | | 16.04 LTS xenial | Fixed 4.15.0-1021.21~16.04.1 | | 14.04 LTS trusty | Not affected | | linux-azure-4.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-azure-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-azure-5.4 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-azure-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-azure-edge | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Fixed 4.15.0-1021.21 | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-azure-fde | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Ignored end of standard support, was ignored [superseded by linux-azure-fde-5.15] | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-azure-fde-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-bluefield | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-euclid | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Ignored end of standard support | | 14.04 LTS trusty | Not in release | | linux-fips | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy FIPS Updates | Not affected | | 20.04 LTS focal FIPS | Not affected | | 18.04 LTS bionic FIPS | Not affected | | 16.04 LTS xenial FIPS | Fixed 4.4.0-1017.22~recert1 | | 14.04 LTS trusty | Not in release | | linux-flo | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Ignored end of standard support | | 14.04 LTS trusty | Not in release | | linux-gcp | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Fixed 4.15.0-1017.18 | | 16.04 LTS xenial | Fixed 4.15.0-1017.18~16.04.1 | | 14.04 LTS trusty | Not in release | | linux-gcp-4.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-gcp-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-gcp-5.4 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-gcp-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-gcp-edge | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-gke | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Ignored end of kernel support | | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Ignored end of standard support, was needs-triage | | 14.04 LTS trusty | Not in release | | linux-gkeop | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-gkeop-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-goldfish | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Ignored end of standard support, was needed | | 14.04 LTS trusty | Not in release | | linux-grouper | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-hwe | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Fixed 4.15.0-32.35~16.04.1 | | 14.04 LTS trusty | Not in release | | linux-hwe-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-hwe-5.4 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-hwe-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-hwe-edge | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Fixed 4.15.0-32.35~16.04.1 | | 14.04 LTS trusty | Not in release | | linux-ibm | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-ibm-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-ibm-5.4 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-intel | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-intel-iot-realtime | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy Real-time | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-intel-iotg | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-intel-iotg-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-iot | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-kvm | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Fixed 4.15.0-1019.19 | | 16.04 LTS xenial | Fixed 4.4.0-1031.37 | | 14.04 LTS trusty | Not in release | | linux-lowlatency | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-lowlatency-hwe-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-lowlatency-hwe-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-lts-trusty | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-lts-utopic | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-lts-vivid | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-lts-wily | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-lts-xenial | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Fixed 4.4.0-133.159~14.04.1 | | linux-maguro | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-mako | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Ignored end of standard support | | 14.04 LTS trusty | Not in release | | linux-manta | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-nvidia | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-nvidia-6.5 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-nvidia-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-nvidia-lowlatency | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-oem | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Fixed 4.15.0-1015.18 | | 16.04 LTS xenial | Ignored end of standard support, was needed | | 14.04 LTS trusty | Not in release | | linux-oem-6.11 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-oem-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-oracle | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not affected | | 14.04 LTS trusty | Not in release | | linux-oracle-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-oracle-5.4 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-oracle-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-raspi | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-raspi-5.4 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-raspi-realtime | 24.10 oracular | Not in release | | 24.04 LTS noble Real-time | Not affected | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-raspi2 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Ignored end of standard support, was ignored [replaced by linux-raspi] | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not affected | | 14.04 LTS trusty | Not in release | | linux-realtime | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy Real-time | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-riscv | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 22.04 LTS jammy | Ignored end of kernel support | | 20.04 LTS focal | Ignored end of standard support, was ignored [superseded by linux-riscv-5.8] | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-riscv-5.15 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-riscv-6.8 | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not in release | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | linux-snapdragon | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not in release | | 20.04 LTS focal | Not in release | | 19.04 disco | Not in release | | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not affected | | 14.04 LTS trusty | Not in release | | linux-xilinx-zynqmp | 24.10 oracular | Not in release | | 24.04 LTS noble | Not in release | | 22.04 LTS jammy | Not affected | | 20.04 LTS focal | Not affected | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | --- * [How can I get the fixes?](https://ubuntu.com/security/cves/about#security) * [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses) * [Patch details](https://ubuntu.com/security/CVE-2018-3646?format=md#patch-details) ## Notes --- ### [tyhicks](https://launchpad.net/~tyhicks) A microcode update will be provided to allow the kernel to flush the L1D cache on VM entry. However, the kernel has a software fallback mechanism in place when microcode updates are not available/installed. The break-fix lines for this CVE are not complete since a large number of patches are required to mitigate this issue. The commit(s) listed are chosen as placeholders for automated CVE triage purposes. ### Patch details For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security) | Package | Patch details | | --- | --- | | linux | * Introduced by [1da177e](https://git.kernel.org/linus/1da177e4c3f41524e886b7f1b8a0c1fc7321cac2), fixed by [c595cee](https://git.kernel.org/linus/c595ceee45707f00f64f61c54fb64ef0cc0b4e85|local-2018-3646-fix) | ## Severity score breakdown CVSS version: CVSS v3.0 **Base score** 5.6 · Medium * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Local | | Attack complexity | High | | Privileges required | Low | | User interaction | None | | Scope | Changed | | Confidentiality impact | High | | Integrity impact | None | | Availability impact | None | * Scores | Parameter | Value | | --- | --- | | Base score | 5.6 · Medium | | Exploitability score | - | | Impact score | - | **Vector:** CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-3646) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-3646) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-3646) * [Debian](https://security-tracker.debian.org/tracker/CVE-2018-3646) ### Related Ubuntu Security Notices (USN) + [USN-3756-1](https://usn.ubuntu.com/USN-3756-1) + Intel Microcode vulnerabilities + 27 August 2018 + [USN-3742-1](https://usn.ubuntu.com/USN-3742-1) + Linux kernel vulnerabilities + 14 August 2018 + [USN-3742-2](https://usn.ubuntu.com/USN-3742-2) + Linux kernel (Trusty HWE) vulnerabilities + 14 August 2018 + [USN-3823-1](https://usn.ubuntu.com/USN-3823-1) + Linux kernel vulnerabilities + 15 November 2018 + [USN-3741-2](https://usn.ubuntu.com/USN-3741-2) + Linux kernel (Xenial HWE) vulnerabilities + 14 August 2018 + [USN-3741-1](https://usn.ubuntu.com/USN-3741-1) + Linux kernel vulnerabilities + 14 August 2018 + [USN-3740-2](https://usn.ubuntu.com/USN-3740-2) + Linux kernel (HWE) vulnerabilities + 14 August 2018 + [USN-3740-1](https://usn.ubuntu.com/USN-3740-1) + Linux kernel vulnerabilities + 14 August 2018 ### Other references * *