# CVE-2021-4028: kernel-rt-debug: The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high...

CVE-2021-4028 is fixed in 43 products on 1 platform, first by RHSA-2022:1550, released April 26, 2022. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-4028
- Priority: High
- CVSS: 7.8 (Important)
- EPSS: 0.0032
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 26, 2022

## 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: use-after-free in RDMA listen() (CVE-2021-4028)  * kernel: heap out of bounds write in nf_dup_netdev.c (CVE-2022-25636)  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-8.5.z4 source tree (BZ#2067266)

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bpftool RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | bpftool ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel rocky 8 | 0:4.18.0-348.23.1.el8_5 | [RLSA-2022:1550](https://patchblox.com/security/data/fix/linux/rlsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-abi-stablelists RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-abi-stablelists ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-core RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-core ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-cross-headers ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-debug RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-debug ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-debug-core RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-debug-core ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-debug-devel RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-debug-devel ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-debug-modules RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-debug-modules ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-debug-modules-extra RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-debug-modules-extra ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-devel RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-devel ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-doc RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-doc ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-headers ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-modules RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-modules ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-modules-extra RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-modules-extra ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-rt RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt rocky 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RLSA-2022:1555](https://patchblox.com/security/data/fix/linux/rlsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-core RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-debug RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-debug-core RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-debug-devel RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-debug-kvm RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-debug-modules RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-debug-modules-extra RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-devel RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-kvm RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-modules RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-rt-modules-extra RHEL 8 | 0:4.18.0-348.23.1.rt7.153.el8_5 | [RHSA-2022:1555](https://patchblox.com/security/data/fix/linux/rhsa-2022-1555.md) | Apr 26, 2022 |
| Linux | kernel-tools RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-tools ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-tools-libs RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-tools-libs ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-tools-libs-devel RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-tools-libs-devel almalinux 8 | 4.18.0-348.23.1.el8_5 | [ALSA-2022:1550](https://patchblox.com/security/data/fix/linux/alsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-tools-libs-devel ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | kernel-zfcpdump RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-zfcpdump-core RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-zfcpdump-devel RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-zfcpdump-modules RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kernel-zfcpdump-modules-extra RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | kpatch-patch-4_18_0-348 RHEL 8 | 0:1-4.el8 | [RHSA-2022:1535](https://patchblox.com/security/data/fix/linux/rhsa-2022-1535.md) | Apr 26, 2022 |
| Linux | kpatch-patch-4_18_0-348_12_2 RHEL 8 | 0:1-2.el8_5 | [RHSA-2022:1535](https://patchblox.com/security/data/fix/linux/rhsa-2022-1535.md) | Apr 26, 2022 |
| Linux | kpatch-patch-4_18_0-348_20_1 RHEL 8 | 0:1-1.el8_5 | [RHSA-2022:1535](https://patchblox.com/security/data/fix/linux/rhsa-2022-1535.md) | Apr 26, 2022 |
| Linux | kpatch-patch-4_18_0-348_2_1 RHEL 8 | 0:1-3.el8_5 | [RHSA-2022:1535](https://patchblox.com/security/data/fix/linux/rhsa-2022-1535.md) | Apr 26, 2022 |
| Linux | kpatch-patch-4_18_0-348_7_1 RHEL 8 | 0:1-3.el8_5 | [RHSA-2022:1535](https://patchblox.com/security/data/fix/linux/rhsa-2022-1535.md) | Apr 26, 2022 |
| Linux | linux Debian 12.15 (bookworm) | 5.14.12-1 | [DEBIAN-CVE-2021-4028](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4028.md) | Aug 24, 2022 |
| Linux | linux Debian 13.5 (trixie) | 5.14.12-1 | [DEBIAN-CVE-2021-4028](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4028.md) | Aug 24, 2022 |
| Linux | linux Debian 14 | 5.14.12-1 | [DEBIAN-CVE-2021-4028](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4028.md) | Aug 24, 2022 |
| Linux | perf RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | perf ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |
| Linux | python3-perf RHEL 8 | 0:4.18.0-348.23.1.el8_5 | [RHSA-2022:1550](https://patchblox.com/security/data/fix/linux/rhsa-2022-1550.md) | Apr 26, 2022 |
| Linux | python3-perf ol 8 | 0:4.18.0-348.23.1.el8_5 | [ELSA-2022-1550](https://patchblox.com/security/data/fix/linux/elsa-2022-1550.md) | Apr 27, 2022 |

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