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CVE-2026-45867 Linux CVE debrief

A use-after-free vulnerability exists in the Linux kernel's ACT8945A power supply driver. The issue stems from incorrect ordering of devm-managed resource allocations: the IRQ is requested before the power_supply handle is registered, causing the power_supply to be freed before the IRQ handler is unregistered during driver removal. This creates a race condition where a late interrupt can invoke power_supply_changed() with a freed handle, leading to system crashes or memory corruption. A similar race exists during probe() where an interrupt may fire before power_supply registration completes, resulting in use of an uninitialized handle. The fix reorders the IRQ request to occur after power_supply registration, ensuring proper teardown sequence.

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-27
Original CVE updated
2026-06-25
Advisory published
2026-05-27
Advisory updated
2026-06-25

Who should care

Linux kernel maintainers, embedded systems developers using ACT8945A power management ICs, distribution security teams, and organizations running Linux on hardware with ACT8945A components

Technical summary

The ACT8945A power supply driver in the Linux kernel incorrectly orders devm-managed resource allocations. When devm_request_irq() is called before devm_power_supply_register(), the automatic cleanup during driver removal frees the power_supply structure before unregistering the IRQ handler. This creates a window where a pending interrupt can execute the handler with a dangling pointer. The handler's call to power_supply_changed() then operates on freed memory. During probe(), a similar race allows interrupts before power_supply initialization to use uninitialized data. The resolution ensures power_supply registration precedes IRQ request, guaranteeing that IRQ teardown occurs before power_supply destruction.

Defensive priority

high

Recommended defensive actions

  • Apply kernel patches from stable trees (commits referenced in source references)
  • Verify IRQ registration ordering in custom ACT8945A driver implementations
  • Review other power supply drivers for similar devm resource ordering issues
  • Monitor kernel logs for crashes during driver probe/removal on ACT8945A-equipped systems

Evidence notes

Vulnerability description and fix details sourced from official CVE record and NVD entry published 2026-05-27. Multiple stable kernel tree commits referenced indicating backports to various kernel versions.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-45867 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-45867

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

  • CVE-2026-45867 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-45867

    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/0768e8525a46df103647ca5059b32320d7fd17e4

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/3291c51d4684d048dd2eb91b5b65fcfdaf72141f

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/697bb5dc0cb4791e244f3970b067bc1ef33be9d9

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/76a42ba547a9b2e2337894f67a4d9247445007d5

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/83c1bd466c514cb24ca6ef347c5aac76a13c4e1e

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/d023ef9f748b2090f7a9dbdd5c622b6ad99088ea

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/f27eb76def5c07e4d7cc468b40741f19dafc83ce

    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.