CVE-2026-64157 netfs: Fix partial invalidation of streaming-write folio

What is CVE-2026-64157?

CVE-2026-64157 is a medium-severity vulnerability in Linux kernel, published on 19 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

netfs: Fix partial invalidation of streaming-write folio

In netfs_invalidate_folio(), if the region of a partial invalidation overlaps the front (but not all) of a dirty write cached in a streaming write page (dirty, but not uptodate, with the dirty region tracked by a netfs_folio struct), the function modifies the dirty region - but incorrectly as it moves the region forward by setting the start to the start, not the end, of the invalidation region.

Fix this by setting finfo->dirty_offset to the end of the invalidation region (iend).

Which versions are affected by CVE-2026-64157?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-64157?

Apply the vendor's patch.

Is CVE-2026-64157 being exploited?

There is no known exploitation of CVE-2026-64157 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-64157, DEBIAN-CVE-2026-64157, GHSA-5p79-2gj5-h84m, UBUNTU-CVE-2026-64157.