CVE-2026-99250 json
printk: Postpone kthread startup
published 2026-11-03 5 d ago modified 2026-11-03 5 d ago also EUVD-2026-115761
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 4%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- Linux Linux 6.12.115, 6.18.59, 7.2.13, 7.3
- linux Debian 13 6.12.115-1
- linux Debian 14 7.2.13-1
debian advisories DEBIAN-CVE-2026-99250
- linux Ubuntu 26.10 7.3.0-10.10
- linux-aws Ubuntu 26.10 7.3.0-1004.4
- linux-gcp Ubuntu 26.10 7.3.0-1004.4
- linux-raspi Ubuntu 26.10 7.3.0-1004.4
- linux-riscv Ubuntu 26.10 7.3.0-10.10.1
- linux-oracle Ubuntu 26.10 7.3.0-1004.4
- linux-realtime Ubuntu 26.10 7.3.0-10.10.1
ubuntu advisories UBUNTU-CVE-2026-99250
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
Exploit prediction
0.16% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
Classification
- Technology feeds
References
Sources
- CVE List CVE-2026-99250
- NVD CVE-2026-99250
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