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CVE-2026-72492 Linux CVE debrief

A use-after-free vulnerability was found in the Linux kernel's ksmbd implementation. The same_client_has_lease function returns an opinfo pointer from ci->m_op_list after dropping ci->m_lock without taking a reference. This can lead to a use-after-free when smb_grant_oplock dereferences the pointer in copy_lease and when checking breaking_cnt. The vulnerability was resolved in the Linux kernel. To verify, defenders should review the official advisory and assess their Linux kernel deployments for potential exposure. The source item is from the NVD modified API. Multiple source references are provided, including several Git commit hashes. Linux kernel developers should review and apply patches. The CVE record was published on 2026-08-15T06:22:23.533Z and has not been modified since then.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-15
Original CVE updated
2026-08-15
Advisory published
2026-08-15
Advisory updated
2026-08-15

Who should care

Linux kernel developers and maintainers, Linux distribution vendors, and users of Linux-based systems, particularly those responsible for managing and securing Linux kernel deployments, should review and apply patches. Additionally, affected operator, platform, vulnerability-management, and security-team impact should be assessed.

Technical summary

The same_client_has_lease function in the Linux kernel's ksmbd implementation returns an opinfo pointer from ci->m_op_list after dropping ci->m_lock without taking a reference. This can lead to a use-after-free when smb_grant_oplock dereferences the pointer in copy_lease and when checking breaking_cnt. To fix this, take a reference when same_client_has_lease selects an existing lease, drop any previous match while scanning, and release the returned reference in smb_grant_oplock after copying the lease state. Affected Linux kernel developers should review and apply patches.

Defensive priority

Medium

Recommended defensive actions

  • Review and apply the provided patches to the Linux kernel
  • Monitor for any potential exploitation attempts
  • Consider implementing additional security controls to mitigate the risk of use-after-free vulnerabilities
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability was resolved in the Linux kernel. The source item is from the NVD modified API. Multiple source references are provided, including several Git commit hashes. To verify, defenders should review the official advisory and assess their Linux kernel deployments for potential exposure.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-72492 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-72492

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

  • CVE-2026-72492 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-72492

    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/09634cd055d9bd8dd167995ea52bcd8028dd5dac

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/0ff82a9cf9312678d8bc4edeef0b6e82659ac12a

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/35d3d6ff2bc1e7aaecb15d5377ebbd6227acae0d

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/65b655f65c3ca1ab5d598d3832bb0ff531725858

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/79c7c59bb519db6f5a2a151965e825ec725614cc

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/7c3264d273d524aa6adcce23c01087271f13586f

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/aaa3bb2bbf2ccbfea9e4e0b9dabf3afc60b50cd0

    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.