CVE-2026-99250
Received
Received - Intake
Kernel Boot Hang Fixed with Delayed Printk Kthread Startup
Vulnerability report for CVE-2026-99250, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-03
Last updated on: 2026-11-03
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
printk: Postpone kthread startup
There have been various bug reports related to SMP systems hanging
on boot. The reports vary but seem to have some overlap with regard
to missed IPI's during SMP setup. The reports also show that
reverting NBCON console usage allows the bugs to disappear.
The NBCON kthreads for console printing are started very early
during boot using early_initcall(). Since these kthreads are
asynchronously enabling/disabling interrupts during early boot, they
may be interfering with early SMP setup on some hardware platforms.
Starting the console printing kthreads later has shown to avoid the
hanging on systems that could previously reproduce the issue.
Postpone kthread starting until after all arch initcalls have
completed.
CVSS Scores
EPSS Scores
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Meta Information
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
