# CVE-2026-53015: erofs: unify lcn as u64 for 32-bit platforms

CVE-2026-53015 is fixed in 50 products on 1 platform, first by ALAS2023-2026-1894, released June 22, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-53015
- Priority: Routine
- CVSS: 5.5 (Moderate)
- EPSS: 0.0012
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 22, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-53015

## Description

In the Linux kernel, the following vulnerability has been resolved:  erofs: unify lcn as u64 for 32-bit platforms  As sashiko reported [1], `lcn` was typed as `unsigned long` (or `unsigned int` sometimes), which is only 32 bits wide on 32-bit platforms, which causes `(lcn << lclusterbits)` to be truncated at 4 GiB.  In order to consolidate the logic, just use `u64` consistently around the codebase.  [1] https://sashiko.dev/r/20260420034612.1899973-1-hsiangkao%40linux.alibaba.com

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bpftool6.12 amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | bpftool6.12-debuginfo amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | bpftool6.18 amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | bpftool6.18-debuginfo amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | dtb-aarch64 opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-64kb opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-64kb sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-azure opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-azure sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-default opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-default sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-default-base opensuse-leap 16.0 | 6.12.0-160000.36.1.160000.2.17 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-default-base sles 16.0 | 6.12.0-160000.36.1.160000.2.17 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-docs opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-docs sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-kvmsmall opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-kvmsmall sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-livepatch-6.12.92-122.166 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel-livepatch-6.18.33-63.124 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel-obs-build opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-obs-qa opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-obs-qa sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-rt opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-source opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-source sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-syms opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-syms sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel-zfcpdump opensuse-leap 16.0 | 6.12.0-160000.36.1 | [OPENSUSE-SU-2026:21388-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21388-1.md) | Jul 21, 2026 |
| Linux | kernel-zfcpdump sles 16.0 | 6.12.0-160000.36.1 | [SUSE-SU-2026:22835-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22835-1.md) | Jul 21, 2026 |
| Linux | kernel6.12 amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-debuginfo amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-debuginfo-common-aarch64 amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-debuginfo-common-x86_64 amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-devel amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-headers amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-modules-extra amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-modules-extra-common amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-tools amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-tools-debuginfo amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.12-tools-devel amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | kernel6.18 amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-debuginfo amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-debuginfo-common-aarch64 amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-debuginfo-common-x86_64 amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-devel amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-headers amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-modules-extra amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-modules-extra-common amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-tools amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-tools-debuginfo amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | kernel6.18-tools-devel amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.94-1 | [DEBIAN-CVE-2026-53015](https://patchblox.com/security/data/fix/linux/debian-cve-2026-53015.md) | Jun 25, 2026 |
| Linux | linux Debian 14 | 7.0.10-1 | [DEBIAN-CVE-2026-53015](https://patchblox.com/security/data/fix/linux/debian-cve-2026-53015.md) | Jun 25, 2026 |
| Linux | perf6.12 amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | perf6.12-debuginfo amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | perf6.18 amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | perf6.18-debuginfo amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | python3-perf6.12 amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | python3-perf6.12-debuginfo amzn 2023 | 1:6.12.92-122.166.amzn2023 | [ALAS2023-2026-1894](https://patchblox.com/security/data/fix/linux/alas2023-2026-1894.md) | Jun 22, 2026 |
| Linux | python3-perf6.18 amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |
| Linux | python3-perf6.18-debuginfo amzn 2023 | 1:6.18.33-63.124.amzn2023 | [ALAS2023-2026-1866](https://patchblox.com/security/data/fix/linux/alas2023-2026-1866.md) | Jun 22, 2026 |

---

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