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CVE-2026-46277 Linux CVE debrief

A HIGH severity vulnerability was found in the Linux kernel, with a CVSS score of 7.8. The vulnerability is related to the handling of device folios in the mm/zone_device module. Specifically, the issue arises when trying to access a device folio after it has been freed, which can lead to unexpected behavior. The vulnerability has been resolved by using a local stack variable instead of touching the folio again to extract the pgmap when calling percpu_ref_put_many().

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-08
Original CVE updated
2026-07-23
Advisory published
2026-06-08
Advisory updated
2026-07-23

Who should care

Users of the Linux kernel should be aware of this vulnerability and take steps to ensure their systems are updated with the patched version.

Technical summary

The vulnerability is caused by the fact that the contents of a device folio can immediately change after calling ->folio_free(), as the folio may be reallocated by a driver with a different order. To fix this issue, the code now uses a local stack variable when calling percpu_ref_put_many() instead of touching the folio again to extract the pgmap.

Defensive priority

high

Recommended defensive actions

  • Update to the latest version of the Linux kernel that includes the patch for this vulnerability. Refer to [cve-org] for more information.
  • Review and apply the patches provided by the Linux kernel maintainers, available at [ref-4] and [ref-5].

Evidence notes

The CVE record [cve-org] provides an official description of the vulnerability. Additional information can be found in the NVD detail page [nvd]. The vulnerability was reported and resolved through the Linux kernel development process, with references [ref-4] and [ref-5] providing more details about the patches applied.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-46277 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-46277

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-46277 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-46277

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/39928984956037cabd304321cb8f342e47421db5

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/85be0a262e39c706edb53c88af8afde2e98222ba

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.