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CVE-2026-43020

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: validate LTK enc_size on load Load Long Term Keys stores the user-provided enc_size and later uses it to size fixed-size stack operations when replying to LE LTK requests. An enc_size larger than the 16-byte key buffer can therefore overflow the reply stack buffer. Reject oversized enc_size values while validating the management LTK record so invalid keys never reach the stored key state.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-01 15:16:46.233000
Last modified
2026-11-06 16:18:16.707000
View original CVE JSON
{
  "id": "CVE-2026-43020",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-05-01T15:16:46.233",
  "lastModified": "2026-11-06T16:18:16.707",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: MGMT: validate LTK enc_size on load\n\nLoad Long Term Keys stores the user-provided enc_size and later uses\nit to size fixed-size stack operations when replying to LE LTK\nrequests. An enc_size larger than the 16-byte key buffer can therefore\noverflow the reply stack buffer.\n\nReject oversized enc_size values while validating the management LTK\nrecord so invalid keys never reach the stored key state."
    }
  ],
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  "metrics": {
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          "scope": "UNCHANGED",
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          "role": "CISA Coordinator",
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  "weaknesses": [
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      "source": "[email protected]",
      "type": "Primary",
      "description": [
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