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PatchSiren cyber security CVE debrief

CVE-2026-98832 Linux CVE debrief

A Linux kernel vulnerability has been identified in blk-cgroup, where saving IRQ state in blkg_tryget_closest() can prevent a potential deadlock. The vulnerability arises when bio_set_dev() associates a bio with a blkg through bio_associate_blkg(). If the blkg lookup misses, blkg_tryget_closest() takes q->queue_lock with spin_lock_irq() and releases it with spin_unlock_irq(), which unconditionally enables local interrupts. This can cause an I/O completion softirq to run on the same CPU, re-acquire pool->lock, and deadlock.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-10-18
Original CVE updated
2026-10-19
Advisory published
2026-10-18
Advisory updated
2026-10-19

Who should care

Linux system administrators, security teams, and operators should assess exposure and prioritize verification of affected systems, especially those with Linux kernel versions 7.2 or earlier. They should review Linux kernel versions, verify if the system is using a vulnerable version, and apply patches or updates to fix the vulnerability. Additionally, they should monitor system logs for potential deadlock occurrences and implement compensating controls to

Why it matters

Linux system administrators and security teams should assess exposure and prioritize verification of affected systems, especially those with Linux kernel versions 7.2 or earlier, to prevent potential deadlock in blk-cgroup.

  • Potential deadlock in blk-cgroup
  • Need to verify affected Linux kernel versions
  • Possible impact on system stability and performance
  • Requires patching or updates to fix the vulnerability

Technical summary

The vulnerability is caused by the unconditional enabling of local interrupts in blkg_tryget_closest(). This can lead to a deadlock when an I/O completion softirq runs on the same CPU and re-acquires pool->lock. The issue arises in the Linux kernel's blk-cgroup, specifically in the blkg_tryget_closest() function. Saving IRQ state in this function can prevent the potential deadlock. The vulnerability affects Linux kernel versions 7.2 or earlier, and system administrators should assess exposure and prioritize verification of affected systems.

Defensive priority

Linux system administrators and security teams should assess exposure and prioritize verification of affected systems, especially those with Linux kernel versions 7.2 or earlier.

Recommended defensive actions

  • Review Linux kernel versions and identify systems that may be affected
  • Verify if the system is using a vulnerable version of the Linux kernel
  • Apply patches or updates to fix the vulnerability
  • Monitor system logs for potential deadlock occurrences
  • Perform vulnerability assessment and prioritize patching for Linux kernel versions 7.2 or earlier
  • Implement compensating controls to mitigate potential impact
  • Track patch deployment and verify remediation for affected systems

Evidence notes

The CVE record and source item provide details on the vulnerability, including its description and affected versions. However, the corpus does not establish versions, exploitation, impact, or remediation beyond known affected scope.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-98832 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-98832

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

  • CVE-2026-98832 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-98832

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

Supplemental references

  • blk-cgroup: save IRQ state in blkg_tryget_closest()

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/98xxx/CVE-2026-98832.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/9fcf4317384ce6758c3127a6e8914c54cbb9c8cc

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/327c428ba79b13e4cc5253333a9d5c0aa5579bdf

    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.