# RHSA-2023:5255: Security update for 12 packages

RHSA-2023:5255, released September 19, 2023, fixes 9 CVEs across 12 products. None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2023-5255
- Platform: Linux
- Released: Sep 19, 2023
- Priority: High (Closes CVE-2023-20593, high severity)
- CVEs: 9, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://access.redhat.com/errata/RHSA-2023:5255

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [kernel-rt](https://patchblox.com/security/data/product/linux/kernel-rt.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-core](https://patchblox.com/security/data/product/linux/kernel-rt-core.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-debug](https://patchblox.com/security/data/product/linux/kernel-rt-debug.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-debug-core](https://patchblox.com/security/data/product/linux/kernel-rt-debug-core.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-debug-devel](https://patchblox.com/security/data/product/linux/kernel-rt-debug-devel.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-debug-kvm](https://patchblox.com/security/data/product/linux/kernel-rt-debug-kvm.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-debug-modules](https://patchblox.com/security/data/product/linux/kernel-rt-debug-modules.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-debug-modules-extra](https://patchblox.com/security/data/product/linux/kernel-rt-debug-modules-extra.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-devel](https://patchblox.com/security/data/product/linux/kernel-rt-devel.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-kvm](https://patchblox.com/security/data/product/linux/kernel-rt-kvm.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-modules](https://patchblox.com/security/data/product/linux/kernel-rt-modules.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |
| [kernel-rt-modules-extra](https://patchblox.com/security/data/product/linux/kernel-rt-modules-extra.md) | RHEL 8 | 0:4.18.0-477.27.1.rt7.290.el8_8 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2023-20593](https://patchblox.com/security/data/cve/CVE-2023-20593.md) | High | amd64-microcode: An issue in “Zen 2” CPUs, under specific microarchitectural circumstances,may allow an attacker to potentially access... | 7.8 | 0.0507 |  |
| [CVE-2023-35001](https://patchblox.com/security/data/cve/CVE-2023-35001.md) | High | bpftool: The kernel packages contain the Linux kernel, the core of any Linux operating system.  Security Fix(es):  * kernel: i... | 7.8 | 0.0154 |  |
| [CVE-2023-2002](https://patchblox.com/security/data/cve/CVE-2023-2002.md) | High | kernel-zfcpdump-devel: The kernel packages contain the Linux kernel, the core of any Linux operating system.  Security Fix(es):  * kernel: i... | 7.8 | 0.0147 |  |
| [CVE-2023-4004](https://patchblox.com/security/data/cve/CVE-2023-4004.md) | High | bpftool: The kernel packages contain the Linux kernel, the core of any Linux operating system.  Security Fix(es):  * kernel: i... | 7.8 | 0.0092 |  |
| [CVE-2023-3390](https://patchblox.com/security/data/cve/CVE-2023-3390.md) | High | linux: A use-after-free vulnerability was found in the Linux kernel's netfilter subsystem in net/netfilter/nf_tables_api.c | 7.8 | 0.0091 |  |
| [CVE-2023-35788](https://patchblox.com/security/data/cve/CVE-2023-35788.md) | High | linux: An issue was discovered in fl_set_geneve_opt in net/sched/cls_flower.c in the Linux kernel before 6.3.7 | 7.8 | 0.0052 |  |
| [CVE-2023-3776](https://patchblox.com/security/data/cve/CVE-2023-3776.md) | High | kernel-abi-stablelists: The kernel packages contain the Linux kernel, the core of any Linux operating system.  Security Fix(es):  * kernel: i... | 7.8 | 0.0051 |  |
| [CVE-2023-3090](https://patchblox.com/security/data/cve/CVE-2023-3090.md) | High | kernel-core: The kernel packages contain the Linux kernel, the core of any Linux operating system.  Security Fix(es):  * kernel: i... | 7.8 | 0.0048 |  |
| [CVE-2023-1637](https://patchblox.com/security/data/cve/CVE-2023-1637.md) | Routine | kernel-core: The kernel packages contain the Linux kernel, the core of any Linux operating system.  Security Fix(es):  * kernel: i... | 5.5 | 0.0022 |  |

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Data as of 2026-11-07T12:40:37Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo