CVE-2026-43020 (GCVE-0-2026-43020)

Vulnerability from cvelistv5 – Published: 2026-05-01 14:15 – Updated: 2026-05-01 14:15
VLAI?
Title
Bluetooth: MGMT: validate LTK enc_size on load
Summary
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 ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 346af67b8d116f01ef696fd47959a55deb2db8b6 , < 0f37d1e65c6d71ad94ccfb5c602163c525db789d (git)
Affected: 346af67b8d116f01ef696fd47959a55deb2db8b6 , < 257cdb960d8ff6d60bb6461b03c814b6cf0c9e64 (git)
Affected: 346af67b8d116f01ef696fd47959a55deb2db8b6 , < c34577f517b556fb6ca173d45bf7e766ae2564ce (git)
Affected: 346af67b8d116f01ef696fd47959a55deb2db8b6 , < f71695e81f4cb428f3c7e2138eae88199005b52c (git)
Affected: 346af67b8d116f01ef696fd47959a55deb2db8b6 , < 82f342b3b006ca1d65f4890c05f2ec32fcb808b6 (git)
Affected: 346af67b8d116f01ef696fd47959a55deb2db8b6 , < 50fb64defa72a3fecd0af1ca7c6b47b5c5c2b257 (git)
Affected: 346af67b8d116f01ef696fd47959a55deb2db8b6 , < 40ba329e8b4cd2fb11b0caf5e6a543ceaebb6009 (git)
Affected: 346af67b8d116f01ef696fd47959a55deb2db8b6 , < b8dbe9648d69059cfe3a28917bfbf7e61efd7f15 (git)
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    Linux Linux Affected: 3.4
Unaffected: 0 , < 3.4 (semver)
Unaffected: 5.10.253 , ≤ 5.10.* (semver)
Unaffected: 5.15.203 , ≤ 5.15.* (semver)
Unaffected: 6.1.168 , ≤ 6.1.* (semver)
Unaffected: 6.6.134 , ≤ 6.6.* (semver)
Unaffected: 6.12.81 , ≤ 6.12.* (semver)
Unaffected: 6.18.22 , ≤ 6.18.* (semver)
Unaffected: 6.19.12 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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{
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          "product": "Linux",
          "programFiles": [
            "net/bluetooth/mgmt.c"
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        }
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          "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."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-01T14:15:23.699Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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    "dateReserved": "2026-05-01T14:12:55.975Z",
    "dateUpdated": "2026-05-01T14:15:23.699Z",
    "state": "PUBLISHED"
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      "date": "2026-05-07",
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  }
}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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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.



Detection rules are retrieved from Rulezet.