Vulnerability-Lookup

GHSA-2R72-M44G-F7FH

Vulnerability from github – Published: 2026-11-03 12:31 – Updated: 2026-11-03 12:31

Details

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.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-99250"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-11-03T12:17:31Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nprintk: Postpone kthread startup\n\nThere have been various bug reports related to SMP systems hanging\non boot. The reports vary but seem to have some overlap with regard\nto missed IPI\u0027s during SMP setup. The reports also show that\nreverting NBCON console usage allows the bugs to disappear.\n\nThe NBCON kthreads for console printing are started very early\nduring boot using early_initcall(). Since these kthreads are\nasynchronously enabling/disabling interrupts during early boot, they\nmay be interfering with early SMP setup on some hardware platforms.\n\nStarting the console printing kthreads later has shown to avoid the\nhanging on systems that could previously reproduce the issue.\n\nPostpone kthread starting until after all arch initcalls have\ncompleted.",
  "id": "GHSA-2r72-m44g-f7fh",
  "modified": "2026-11-03T12:31:50Z",
  "published": "2026-11-03T12:31:50Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99250"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5f339c46f153184570f16c8e789c9709b14cbe8b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7595bacee48bc30b5021eccf199d704d4e5e5374"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/792acd173da0884f0172c68cb473f42cf93c647e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a86bcdd84c8fe7a45f73e12d53fe06fea07d1ceb"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-99250 (GCVE-0-2026-99250)

Vulnerability from cvelistv5 – Published: 2026-11-03 11:18 – Updated: 2026-11-03 11:18

Title

printk: Postpone kthread startup

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.

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6637 records in the last 180 days details

References

4 references

URL	Tags
https://git.kernel.org/stable/c/a86bcdd84c8fe7a45…
https://git.kernel.org/stable/c/7595bacee48bc30b5…
https://git.kernel.org/stable/c/792acd173da0884f0…
https://git.kernel.org/stable/c/5f339c46f15318457…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 76f258bf3f2aae570209319944703a92ac64e29e , < a86bcdd84c8fe7a45f73e12d53fe06fea07d1ceb (git) Affected: 76f258bf3f2aae570209319944703a92ac64e29e , < 7595bacee48bc30b5021eccf199d704d4e5e5374 (git) Affected: 76f258bf3f2aae570209319944703a92ac64e29e , < 792acd173da0884f0172c68cb473f42cf93c647e (git) Affected: 76f258bf3f2aae570209319944703a92ac64e29e , < 5f339c46f153184570f16c8e789c9709b14cbe8b (git)
Linux	Linux	Affected: 6.12 Unaffected: 0 , < 6.12 (semver) Unaffected: 6.12.115 , ≤ 6.12.* (semver) Unaffected: 6.18.59 , ≤ 6.18.* (semver) Unaffected: 7.2.13 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)

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JSON

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          "programFiles": [
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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