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Linux KernelOperating system · Linux

CVE-2026-53124

MEDIUM · 5.5 CVSS v3.1 Published 2026-06-24
Fix available
A fix is available. Upgrade to 6.15 / 7.0.10 or later.
See remediation →
57/100
Remediation priority · Elevated
Zero-click Patch available 8 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the Linux kernel, the following vulnerability has been resolved: ublk: reset per-IO canceled flag on each fetch If a ublk server starts recovering devices but dies before issuing fetch commands for all IOs, cancellation of the fetch commands that were successfully issued may never complete. This is because the per-IO canceled flag can remain set even after the fetch for that IO has been submitted - the per-IO canceled flags for all IOs in a queue are reset together only once all IOs for that queue have been fetched. So if a nonempty proper subset of the IOs for a queue are fetched when the ublk server dies, the IOs in that subset will never successfully be canceled, as their canceled flags remain set, and this prevents ublk_cancel_cmd from actually calling io_uring_cmd_done on the commands, despite the fact that they are outstanding. Fix this by resetting the per-IO cancel flags immediately when each IO is fetched instead of waiting for all IOs for the queue (which may never happen).

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

In the Linux kernel's ublk (user block device) subsystem, a race condition exists where per-IO canceled flags are only reset after all IOs in a queue are fetched together. If the ublk server dies during recovery after only a subset of IOs are fetched, those fetched IOs retain their canceled flags, preventing ublk_cancel_cmd from calling io_uring_cmd_done to complete the commands.

MitigationApply the kernel patch that resets per-IO cancel flags immediately upon each individual IO fetch. This is a kernel-level fix requiring a code change and kernel upgrade or vendor patch application.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:>= 6.14.6, < 6.15>= 6.15.1, < 7.0.10= 6.15

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check kernel version against affected ranges
    Run `uname -r` or `cat /proc/version` and compare the version to: >= 6.14.6, < 6.15; >= 6.15.1, < 7.0.10; = 6.15
    Affected if Kernel version falls within any of the affected version ranges
  2. Verify ublk subsystem is loaded or compiled in
    Check if ublk module is loaded with `lsmod | grep ublk` or look for ublk in kernel config at `/boot/config-$(uname -r)`
    Affected if The ublk module is loaded or compiled into the running kernel
  3. Check for active ublk device instances
    List ublk device files with `ls -la /dev/ublk* 2>/dev/null` or check `/sys/kernel/debug/ublk/` for active devices
    Affected if One or more ublk devices exist and are configured
  4. Review system logs for ublk server failures during recovery
    Search kernel logs with `dmesg | grep -i ublk` or check `/var/log/syslog` for ublk server crash messages occurring during device recovery operations
    Affected if Logs show ublk server failures during recovery while running an affected kernel version

A system is affected only if it runs an affected kernel version AND uses the ublk subsystem with active devices, particularly if ublk server failures during recovery have been observed in logs.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 6.15 / 7.0.10 or later
Fixed in 6.157.0.10
Vendor patch git.kernel.org →
Interim mitigation

Apply the kernel patch that resets per-IO cancel flags immediately upon each individual IO fetch. This is a kernel-level fix requiring a code change and kernel upgrade or vendor patch application.

Recommended fix High confidence

Linux Kernel >= 7.0.10

  1. Update the Linux kernel to version 7.0.10 or later using your distribution's package manager or kernel upgrade procedure

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Linux Kernel Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing12.0 h
  • Review / QA6.0 h
30.0 hours of engineering $5,120
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-53124 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data