CVE-2026-68166

In the Linux kernel, the following vulnerability has been resolved: userfaultfd: prevent registration of special VMAs Vova Tokarev says: userfaultfd allows registration on shadow stack VMAs. With userfaultfd access, you can register on the shadow stack, discard a page ... and inject a page with chosen return addresses via UFFDIO_COPY. Update vma_can_userfault() to reject VM_SHADOW_STACK. While on it, also reject VM_SPECIAL so that if a driver would implement vm_uffd_ops, it wouldn't be possible to register special VMAs with userfaultfd. Since VM_SPECIAL includes VM_DONTEXPAND which is set but hugetlb, exclude hugetlb VMAs from the check for VM_SPECIAL.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/0c26202b157f1efc3cd2f26f5c30f59b508a6a5d
https://git.kernel.org/stable/c/165613191ad9d034bf17c00e3a142f9561597ec5
https://git.kernel.org/stable/c/3c58f641e813c3c71039f8fd4d4e2a3aab713288
https://git.kernel.org/stable/c/495a28d5a100be1b232633f4c2dcc42ba10b3796
https://git.kernel.org/stable/c/d974b4b786214883bd8e56bda10b454c80fd6205

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-10 13:20

Updated : 2026-08-23 13:16

NVD link : CVE-2026-68166

Mitre link : CVE-2026-68166

CVE.ORG link : CVE-2026-68166

JSON object : View

Products Affected

No product.

CWE

No CWE.

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