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CVE-2026-53261 Linux CVE debrief

CVE-2026-53261 is a vulnerability in the Linux kernel that involves the release of nested relations in devlink. The vulnerability occurs when a devlink instance is created with a nested relation before registration, but then fails probe before devl_register() is reached. In such cases, the devlink->rel is leaked because devl_unregister() is not called. This vulnerability can be mitigated by releasing any pending relation from devlink_free() as well. The Linux kernel maintainers have addressed this issue by updating the devlink_free() function to release any pending relations.

Vendor
Linux
Product
Unknown
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-25
Original CVE updated
2026-07-08
Advisory published
2026-06-25
Advisory updated
2026-07-08

Who should care

Linux kernel developers, Linux distribution maintainers, and organizations using Linux-based systems should be aware of this vulnerability. They should review their systems and apply patches or mitigations as necessary to prevent exploitation.

Technical summary

The vulnerability is caused by a missing release of nested relations in devlink when a devlink instance fails probe before registration. The devlink relation state is normally released from devl_unregister(), which calls devlink_rel_put(). However, in cases where a devlink instance gets a nested relation before registration and then fails probe, devl_unregister() is not called, leading to a leak of devlink->rel. The fix involves releasing any pending relation from devlink_free() as well.

Defensive priority

High priority should be given to patching or mitigating this vulnerability, especially for systems using the Linux kernel. Linux kernel developers and maintainers should review and apply patches or updates to address this issue.

Recommended defensive actions

  • Review and apply patches or updates to the Linux kernel to address this vulnerability.
  • Ensure that devlink_free() is updated to release any pending relations.
  • Monitor Linux kernel updates and patches for this vulnerability.
  • Perform regular vulnerability assessments and risk evaluations.
  • Implement compensating controls to mitigate potential exploitation.

Evidence notes

The CVE-2026-53261 vulnerability was introduced in the Linux kernel and involves the release of nested relations in devlink. The vulnerability was publicly disclosed on 2026-06-25 and modified on 2026-06-30. The Linux kernel maintainers have addressed this issue by updating the devlink_free() function.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-53261 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-53261

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

  • CVE-2026-53261 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-53261

    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/11324d52b0c63f4f202b35793c6507a575e9a689

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/3522b21fd7e1863d0734537737bd59f1b90d0190

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/927f96861f939c0b517d13ed27bf4fabbfc1cfb3

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/a9137286884703113b1c9e6403bd6d7d97b14754

    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.