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CVE-2026-99034 Linux CVE debrief

A Linux kernel vulnerability was found in the mmc: sdhci-sprd driver. The issue arises from sdhci_sprd_probe() enabling runtime PM without corresponding cleanup in sdhci_sprd_remove(). This can lead to improper clock management if the device is runtime suspended during removal. The fix involves resuming the device, disabling runtime PM, and dropping temporary runtime PM references before disabling clocks.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-10-23
Original CVE updated
2026-10-30
Advisory published
2026-10-23
Advisory updated
2026-10-30

Who should care

Linux system administrators, kernel developers, and teams responsible for maintaining Linux-based infrastructure should be aware of this vulnerability and take steps to verify and apply patches.

Why it matters

This vulnerability affects the Linux kernel's mmc: sdhci-sprd driver and requires verification and patching to prevent potential issues. Linux system administrators and developers should prioritize patching and monitoring.

  • Verification of patch application is required to prevent potential clock management issues
  • Inventory checks are necessary to identify affected systems
  • Monitoring for unusual behavior related to the mmc: sdhci-sprd driver is recommended

Technical summary

The mmc: sdhci-sprd driver in the Linux kernel does not properly handle runtime PM during device removal. This can cause clock management issues if the device is runtime suspended. The fix ensures proper cleanup and clock management during removal by resuming the device, disabling runtime PM, and dropping temporary runtime PM references before disabling clocks. This vulnerability affects Linux system administrators, kernel developers, and teams responsible for maintaining Linux-based infrastructure, who should prioritize verifying and applying patches.

Defensive priority

Defenders should prioritize verifying and applying patches for this vulnerability, especially for systems using the affected driver.

Recommended defensive actions

  • Verify and apply patches from Linux vendors for the mmc: sdhci-sprd driver
  • Inventory Linux systems for use of the affected driver
  • Monitor for potential clock management issues on affected systems
  • 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 identified through manual code inspection of the Linux kernel source code. This involved reviewing the sdhci-sprd driver implementation and identifying the missing runtime PM cleanup in the remove path. The fix ensures proper clock management during device removal, preventing potential issues if the device is runtime suspended. Linux system administrators and developers should verify and apply patches from Linux vendors for the mmc: sdhci-sprd driver. They should also inventory Linux systems for use of the affec

Sources and references

Verified primary and authoritative sources

  • CVE-2026-99034 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-99034

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

  • CVE-2026-99034 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-99034

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

Supplemental references

  • mmc: sdhci-sprd: disable runtime PM on remove

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/99xxx/CVE-2026-99034.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/a0c7facc0fe9ec772cf8bffac2315a8e1311d39a

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/4dce8c272417a564bd8c8d2ea88ef901e5447f22

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/cccd175dd2bfbf8c34a1b0f413760d2ce9ff3ac9

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/605a59639abb9cb63cd7676460461fb0b34756b3

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/03244b8713d044425db5dbee08037ecd79b684f9

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/3a1caa886d41d9bcc9a402906336eda34a90d323

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/dbad91a31c482063c0a87c90aa83c9001972c6ac

    Supplemental source

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.