CVE-2026-64357
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.
Executive briefing
The source record describes: 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. The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.
Evidence confidence: Moderate Evidence-derived, not an exploitability verdict
Severity & attack characteristics
CVSS vector:CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Technical explanation & impact
The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.
Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.
Weakness classification
NVD-CWE-noinfoAffected products and versions
Products below are parsed from NVD vulnerable CPE configuration entries. Version boundaries are shown as published; verify applicability with the vendor.
| Vendor | Product | Version evidence |
|---|---|---|
| linux | linux_kernel | from (inclusive) 6.19; before 7.1.4 |
Remediation & validation
- Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
- Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
- Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
- Validate the remediation with a version check and vulnerability rescan, then retain change evidence.
No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.
Vendor advisories, patches & exploit references
- https://git.kernel.org/stable/c/0a5213bbff62b51c7d4999ac8c7e11ea57d00d45 PATCH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/4707344b0d36d1012c8a1716e20167cd3afdd5f1 PATCH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/a62ef2d13d6e7270dd5e88c6082bf2d0edcd5112 PATCH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/c597c8580d50127fc1221b5a5b653a94d49e23e3 PATCH 416baaa9-dc9f-4396-8d5f-8c081fb06d67