CVE-2026-53266
Linux — Linux Kernel Out-of-Bounds Write Vulnerability
CISA KEV · in the CISA KEV catalog since 2026-09-18
What EVULNABLE says
Listed in the CISA KEV catalog, and an EPSS probability of 0.008.
Patch This Cycle
The priority band answers “how soon”, not “how bad” — see Methodology for what it weighs and where it abstains.
The evidence behind it
| Measure | Value | Source | What it means |
|---|---|---|---|
| CVSS base score | 8.8 | NVD | How severe the flaw is in itself. It does not say how likely an attack is. |
| FIRST EPSS | 0.008 (56.6th pctl) | FIRST | FIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. |
| Actively exploited | Confirmed | CISA KEV | Whether a source of record has confirmed attacks using it in the wild. |
| Ransomware campaign use | Unknown or none | CISA KEV | Whether CISA has seen ransomware operators use it. |
| CISA remediation deadline | 2026-09-21 — CISA federal deadline · Overdue by 26 days | CISA KEV | The date US federal agencies must have fixed or mitigated it. |
| Fixed in | Red Hat Enterprise Linux AppStream (v. 9) -> kernel-64k-debug-debuginfo-0:5.14.0-687.23.1.el9_8.aarch64 | Red Hat Enterprise Linux NFV (v. 8) -> kernel-rt-0:4.18.0-553.143.1.rt7.484.el8_10.src | Red Hat Enterprise Linux BaseOS (v. 8) -> bpftool-0:4.18.0-553.143.1.el8_10.aarch64 | Red Hat Enterprise Linux BaseOS AUS (v.8.6) -> bpftool-0:4.18.0-372.217.1.el8_6.x86_64 | Red Hat Enterprise Linux AppStream (v. 10) -> kernel-64k-debug-debuginfo-0:6.12.0-211.59.1.el10_2.aarch64 | Red Hat Enterprise Linux BaseOS E4S (v.8.8) -> bpftool-0:4.18.0-477.169.1.el8_8.ppc64le | Red Hat Enterprise Linux AppStream EUS (v. 10.0) -> kernel-64k-debug-debuginfo-0:6.12.0-55.106.1.el10_0.aarch64 | Red Hat Enterprise Linux AppStream EUS (v.9.6) -> kernel-64k-debug-debuginfo-0:5.14.0-570.143.1.el9_6.aarch64 | Red Hat Enterprise Linux BaseOS AUS (v.8.4) -> bpftool-0:4.18.0-305.209.1.el8_4.x86_64 | Red Hat Enterprise Linux AppStream E4S (v.9.4) -> bpftool-debuginfo-0:7.3.0-427.152.1.el9_4.aarch64 | Red Hat Enterprise Linux AppStream E4S (v.9.2) -> bpftool-debuginfo-0:7.0.0-284.194.1.el9_2.aarch64 | Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) -> kernel-rt-0:5.14.0-284.194.1.rt14.479.el9_2.src | Red Hat Enterprise Linux for Real Time (v. 7 ELS) -> kernel-rt-0:3.10.0-1160.164.1.rt56.1316.el7.src | Red Hat Enterprise Linux Server (v. 7 ELS) -> bpftool-0:3.10.0-1160.164.1.el7.ppc64 | NVIDIA for RHEL 10 -> kernel-0:6.12.0-231.20.el10nv.aarch64 | Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION) -> kernel-0:2.6.32-754.64.1.el6.i686 | SUSE Liberty Linux 9 -> kernel-0:5.14.0-687.23.1.el9_8.x86_64 | SUSE Liberty Linux 8 -> bpftool-0:4.18.0-553.143.1.el8_10.x86_64 | SUSE Liberty Linux 7 LTSS -> bpftool-0:3.10.0-1160.164.1.el7.x86_64 | SUSE Liberty Linux 10 -> kernel-0:6.12.0-211.61.1.el10_2.x86_64 | SUSE Linux Micro 6.0 -> kernel-default-0:6.4.0-49.1.aarch64 | SUSE Linux Micro 6.0 -> kernel-devel-rt-0:6.4.0-49.1.noarch | SUSE Linux Micro 6.1 -> kernel-default-0:6.4.0-49.1.aarch64 | SUSE Linux Micro 6.1 -> kernel-devel-rt-0:6.4.0-49.1.noarch | SUSE Linux Micro Extras 6.2 -> kernel-obs-build-0:6.12.0-160000.36.1.aarch64 | SUSE Linux Micro 6.2 -> kernel-64kb-0:6.12.0-160000.36.1.aarch64 | SUSE Linux Enterprise High Availability Extension 16.0 -> cluster-md-kmp-default-0:6.12.0-160000.36.1.ppc64le | SUSE Linux Enterprise Server 16.0 -> cluster-md-kmp-default-0:6.12.0-160000.36.1.ppc64le | SUSE Linux Enterprise Live Patching 15 SP7 -> kernel-livepatch-6_4_0-150700_7_62-rt-0:1-150700.1.3.1.x86_64 | Open Enterprise Server 25.4 -> kernel-64kb-0:6.4.0-150700.53.66.1.aarch64 | SUSE Linux Enterprise Live Patching 15 SP6 -> kernel-default-livepatch-0:6.4.0-150600.23.138.1.ppc64le | SUSE Linux Enterprise Micro 5.5 -> kernel-devel-rt-0:5.14.21-150500.13.164.1.noarch | SUSE Linux Enterprise Micro 5.3 -> kernel-rt-0:5.14.21-150400.15.189.1.x86_64 | SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS -> cluster-md-kmp-default-0:5.14.21-150500.55.192.2.aarch64 | Open Enterprise Server 23.4 -> kernel-64kb-0:5.14.21-150400.24.243.1.aarch64 | openSUSE Leap 16.0 -> cluster-md-kmp-64kb-0:6.12.0-160000.36.1.aarch64 | linux -> 6.1.176-1 | linux -> 7.0.13-1 | linux -> 6.12.94-1 | NVD | The version(s) the vendor has published as fixed, where NVD records one. |
| Public exploit module | None known | Metasploit | Module existing is not the same as active exploitation. |
| EUVD cross-reference | Listed | ENISA EUVD | ENISA's own vulnerability database entry for this CVE, where one exists. |
Impacted software or hardware
- linux kernel Operating system — >= 5.4.73 < 5.5, >= 5.8.17 < 5.9, >= 5.9.2 < 5.10.259, >= 5.11 < 5.15.210, >= 5.16 < 6.1.176, >= 6.2 < 6.6.143, >= 6.7 < 6.12.94, >= 6.13 < 6.18.36, >= 6.19 < 7.0.13, 7.1
Fixed versions: Red Hat Enterprise Linux AppStream (v. 9) -> kernel-64k-debug-debuginfo-0:5.14.0-687.23.1.el9_8.aarch64 | Red Hat Enterprise Linux NFV (v. 8) -> kernel-rt-0:4.18.0-553.143.1.rt7.484.el8_10.src | Red Hat Enterprise Linux BaseOS (v. 8) -> bpftool-0:4.18.0-553.143.1.el8_10.aarch64 | Red Hat Enterprise Linux BaseOS AUS (v.8.6) -> bpftool-0:4.18.0-372.217.1.el8_6.x86_64 | Red Hat Enterprise Linux AppStream (v. 10) -> kernel-64k-debug-debuginfo-0:6.12.0-211.59.1.el10_2.aarch64 | Red Hat Enterprise Linux BaseOS E4S (v.8.8) -> bpftool-0:4.18.0-477.169.1.el8_8.ppc64le | Red Hat Enterprise Linux AppStream EUS (v. 10.0) -> kernel-64k-debug-debuginfo-0:6.12.0-55.106.1.el10_0.aarch64 | Red Hat Enterprise Linux AppStream EUS (v.9.6) -> kernel-64k-debug-debuginfo-0:5.14.0-570.143.1.el9_6.aarch64 | Red Hat Enterprise Linux BaseOS AUS (v.8.4) -> bpftool-0:4.18.0-305.209.1.el8_4.x86_64 | Red Hat Enterprise Linux AppStream E4S (v.9.4) -> bpftool-debuginfo-0:7.3.0-427.152.1.el9_4.aarch64 | Red Hat Enterprise Linux AppStream E4S (v.9.2) -> bpftool-debuginfo-0:7.0.0-284.194.1.el9_2.aarch64 | Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) -> kernel-rt-0:5.14.0-284.194.1.rt14.479.el9_2.src | Red Hat Enterprise Linux for Real Time (v. 7 ELS) -> kernel-rt-0:3.10.0-1160.164.1.rt56.1316.el7.src | Red Hat Enterprise Linux Server (v. 7 ELS) -> bpftool-0:3.10.0-1160.164.1.el7.ppc64 | NVIDIA for RHEL 10 -> kernel-0:6.12.0-231.20.el10nv.aarch64 | Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION) -> kernel-0:2.6.32-754.64.1.el6.i686 | SUSE Liberty Linux 9 -> kernel-0:5.14.0-687.23.1.el9_8.x86_64 | SUSE Liberty Linux 8 -> bpftool-0:4.18.0-553.143.1.el8_10.x86_64 | SUSE Liberty Linux 7 LTSS -> bpftool-0:3.10.0-1160.164.1.el7.x86_64 | SUSE Liberty Linux 10 -> kernel-0:6.12.0-211.61.1.el10_2.x86_64 | SUSE Linux Micro 6.0 -> kernel-default-0:6.4.0-49.1.aarch64 | SUSE Linux Micro 6.0 -> kernel-devel-rt-0:6.4.0-49.1.noarch | SUSE Linux Micro 6.1 -> kernel-default-0:6.4.0-49.1.aarch64 | SUSE Linux Micro 6.1 -> kernel-devel-rt-0:6.4.0-49.1.noarch | SUSE Linux Micro Extras 6.2 -> kernel-obs-build-0:6.12.0-160000.36.1.aarch64 | SUSE Linux Micro 6.2 -> kernel-64kb-0:6.12.0-160000.36.1.aarch64 | SUSE Linux Enterprise High Availability Extension 16.0 -> cluster-md-kmp-default-0:6.12.0-160000.36.1.ppc64le | SUSE Linux Enterprise Server 16.0 -> cluster-md-kmp-default-0:6.12.0-160000.36.1.ppc64le | SUSE Linux Enterprise Live Patching 15 SP7 -> kernel-livepatch-6_4_0-150700_7_62-rt-0:1-150700.1.3.1.x86_64 | Open Enterprise Server 25.4 -> kernel-64kb-0:6.4.0-150700.53.66.1.aarch64 | SUSE Linux Enterprise Live Patching 15 SP6 -> kernel-default-livepatch-0:6.4.0-150600.23.138.1.ppc64le | SUSE Linux Enterprise Micro 5.5 -> kernel-devel-rt-0:5.14.21-150500.13.164.1.noarch | SUSE Linux Enterprise Micro 5.3 -> kernel-rt-0:5.14.21-150400.15.189.1.x86_64 | SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS -> cluster-md-kmp-default-0:5.14.21-150500.55.192.2.aarch64 | Open Enterprise Server 23.4 -> kernel-64kb-0:5.14.21-150400.24.243.1.aarch64 | openSUSE Leap 16.0 -> cluster-md-kmp-64kb-0:6.12.0-160000.36.1.aarch64 | linux -> 6.1.176-1 | linux -> 7.0.13-1 | linux -> 6.12.94-1
Remediation: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Remediation basis: CISA KEV required action
ENISA EUVD also lists this CVE at CVSS 8.8 (v3.1), assigned by Linux. Source: euvd.enisa.europa.eu.
22 days recorded, 2026-09-24 to 2026-10-15
0.83% as of 2026-10-15 (56.6th percentile). FIRST EPSS, recorded daily since this page started tracking it.
2026-09-24
2026-10-15
What CISA says to do
- This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see:
- git.kernel.org/…/bf84ad7c7a9ede46e31afaa41a1ba06a159e8c87 ↗
- git.kernel.org/…/76280b78cc9f23bdc6438e10ad6dff148ef8375b ↗
- git.kernel.org/…/b7e91939ba9be805a62a257fa4e227dffbb88fa0 ↗
- git.kernel.org/…/afd64b59c3de9bbbdd3759e834fdc55cda716e0b ↗
- git.kernel.org/…/153ea96c806aea395daba907a4f88480b6ad5093 ↗
- git.kernel.org/…/b18675263db1147c8e1cab625400c13a0d87bd2d ↗
- git.kernel.org/…/c9b5ff59feffb92a147a84a5aa28acd2cb8ff4c5 ↗
- git.kernel.org/…/67ba971ae02514d85818fe0c32549ab4bfa3bf49 ↗
- BOD 26-04 ↗
- Forensics Triage Requirements ↗
- nvd.nist.gov/…/CVE-2026-53266 ↗
The primary records
This page is an opinion about urgency. Where it and a source of record disagree, the source of record is the record.
Where this sits
CVE-2026-53266 is one of the entries ranked on the priority feed and in the non-Microsoft advisories.