# CVE-2026-64059: linux: In the Linux kernel, the following vulnerability has been resolved:  netfs: Fix folio->private handling in netfs_perf...

CVE-2026-64059 is fixed in 38 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-2026-64059
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0016
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 22, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:  netfs: Fix folio->private handling in netfs_perform_write()  Under some circumstances, netfs_perform_write() doesn't correctly manipulate folio->private between NULL, NETFS_FOLIO_COPY_TO_CACHE, pointing to a group and pointing to a netfs_folio struct, leading to potential multiple attachments of private data with associated folio ref leaks and also leaks of netfs_folio structs or netfs_group refs.  Fix this by consolidating the place at which a folio is marked uptodate in one place and having that look at what's attached to folio->private and decide how to clean it up and then set the new group.  Also, the content shouldn't be flushed if group is NULL, even if a group is specified in the netfs_group parameter, as that would be the case for a new folio.  A filesystem should always specify netfs_group or never specify netfs_group.  The Sashiko auto-review tool noted that it was theoretically possible that the fpos >= ctx->zero_point section might leak if it modified a streaming write folio.  This is unlikely, but with a network filesystem, third party changes can happen.  It also pointed out that __netfs_set_group() would leak if called multiple times on the same folio from the "whole folio modify section".

## 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 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | bpftool6.18-debuginfo amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 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-6.18.35-68.127 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 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 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-debuginfo amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-debuginfo-common-aarch64 amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-debuginfo-common-x86_64 amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-devel amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-headers amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-modules-extra amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-modules-extra-common amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-tools amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-tools-debuginfo amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | kernel6.18-tools-devel amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.94-1 | [DEBIAN-CVE-2026-64059](https://patchblox.com/security/data/fix/linux/debian-cve-2026-64059.md) | Jul 20, 2026 |
| Linux | linux Debian 14 | 7.0.12-1 | [DEBIAN-CVE-2026-64059](https://patchblox.com/security/data/fix/linux/debian-cve-2026-64059.md) | Jul 20, 2026 |
| Linux | microvm-kernel6.18 amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 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 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | perf6.18-debuginfo amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.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 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |
| Linux | python3-perf6.18-debuginfo amzn 2023 | 1:6.18.35-68.127.amzn2023 | [ALAS2023-2026-1881](https://patchblox.com/security/data/fix/linux/alas2023-2026-1881.md) | Jun 22, 2026 |

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Data as of 2026-11-08T13:06:02Z 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

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