# CVE-2021-3653: kernel-rt-debug-modules: The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high...

CVE-2021-3653 is fixed in 47 products on 1 platform, first by RHSA-2021:3548, released September 15, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-3653
- Priority: High
- CVSS: 8.8 (Moderate)
- EPSS: 0.0045
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 15, 2021

## Description

The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.  Security Fix(es):  * kernel: SVM nested virtualization issue in KVM (AVIC support) (CVE-2021-3653)  For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.  Bug Fix(es):  * kernel-rt: update RT source tree to the RHEL-8.4.z source tree (BZ#2001131)

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bpftool RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | bpftool ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-abi-stablelists RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-abi-stablelists ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-core RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-core ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-cross-headers RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-cross-headers ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-debug RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-debug ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-debug-core RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-debug-core ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-debug-devel RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-debug-devel ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-debug-modules RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-debug-modules ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-debug-modules-extra RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-debug-modules-extra ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-devel RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-devel ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-doc RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-doc ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-headers ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-modules RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-modules ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-modules-extra RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-modules-extra ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-rt RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-core RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-debug RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-debug-core RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-debug-devel RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-debug-kvm RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-debug-modules RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-debug-modules-extra RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-devel RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-kvm RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-modules RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-rt-modules-extra RHEL 8 | 0:4.18.0-305.19.1.rt7.91.el8_4 | [RHSA-2021:3547](https://patchblox.com/security/data/fix/linux/rhsa-2021-3547.md) | Sep 15, 2021 |
| Linux | kernel-tools RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-tools ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-tools-libs RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-tools-libs ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-tools-libs-devel RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-tools-libs-devel ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |
| Linux | kernel-uek ol 8 | 0:5.4.17-2136.301.1.2.el8uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | kernel-uek-container ol 8 | 0:5.4.17-2136.301.1.2.el8 | [ELSA-2021-9565](https://patchblox.com/security/data/fix/linux/elsa-2021-9565.md) | Nov 23, 2021 |
| Linux | kernel-uek-container-debug ol 8 | 0:5.4.17-2136.301.1.2.el8 | [ELSA-2021-9565](https://patchblox.com/security/data/fix/linux/elsa-2021-9565.md) | Nov 23, 2021 |
| Linux | kernel-uek-debug ol 8 | 0:5.4.17-2136.301.1.2.el8uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | kernel-uek-debug-devel ol 8 | 0:5.4.17-2136.301.1.2.el8uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | kernel-uek-devel ol 8 | 0:5.4.17-2136.301.1.2.el8uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | kernel-uek-doc ol 8 | 0:5.4.17-2136.301.1.2.el8uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | kernel-uek-tools ol 8 | 0:5.4.17-2136.301.1.2.el7uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | kernel-uek-tools-libs ol 8 | 0:5.4.17-2136.301.1.2.el7uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | kernel-zfcpdump RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-zfcpdump-core RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-zfcpdump-devel RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-zfcpdump-modules RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | kernel-zfcpdump-modules-extra RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | perf RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | perf ol 8 | 0:5.4.17-2136.301.1.2.el7uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | python-perf ol 8 | 0:5.4.17-2136.301.1.2.el7uek | [ELSA-2021-9564](https://patchblox.com/security/data/fix/linux/elsa-2021-9564.md) | Nov 23, 2021 |
| Linux | python3-perf RHEL 8 | 0:4.18.0-305.19.1.el8_4 | [RHSA-2021:3548](https://patchblox.com/security/data/fix/linux/rhsa-2021-3548.md) | Sep 15, 2021 |
| Linux | python3-perf ol 8 | 0:4.18.0-305.19.1.el8_4 | [ELSA-2021-3548](https://patchblox.com/security/data/fix/linux/elsa-2021-3548.md) | Sep 16, 2021 |

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