CVE-2026-64357 xfs: fix exchmaps reservation limit check

What is CVE-2026-64357?

CVE-2026-64357 is a medium-severity vulnerability in Linux kernel, published on 25 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:

xfs: fix exchmaps reservation limit check

xfs_exchmaps_estimate_overhead() adds the bmbt and rmapbt overhead to a local resblks variable, but the final UINT_MAX check still tests req->resblks. That is the reservation value from before the overhead was added.

The computed value is stored back in req->resblks and later passed to xfs_trans_alloc(), whose block reservation argument is unsigned int. Check the computed reservation so the existing limit applies to the value that will be used.

Which versions are affected by CVE-2026-64357?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-64357?

Apply the vendor's patch.

Is CVE-2026-64357 being exploited?

There is no known exploitation of CVE-2026-64357 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-2026-64357, DEBIAN-CVE-2026-64357, GHSA-cgx7-q95q-mhc8, ROOT-OS-UBUNTU-2204-CVE-2026-64357, UBUNTU-CVE-2026-64357.