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CVE-2026-74529 (GCVE-0-2026-74529)

Vulnerability from cvelistv5 – Published: 2026-08-15 12:27 – Updated: 2026-08-17 05:48
VLAI
Title
Bluetooth: hci_sync: hold conn in hci_connect_pa_sync() callback
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: hold conn in hci_connect_pa_sync() callback There is theoretical UAF if the conn is freed while the hci_sync task is running. Hold refcount to avoid that.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 6d0417e4e1cf66fd917f06f0454958362714ef7d , < c53c70ec289ee12f20c4f1b2fbfd151762c01f67 (git)
Affected: 6d0417e4e1cf66fd917f06f0454958362714ef7d , < 44fc74069d8988f2825246f9401218e29de2c0ab (git)
Affected: eb8b860e87b296bd1874c79a668081efd00f9754 (git)
Affected: 94bf6380e936339a700c0b3171a49baf512aa70b (git)
Affected: 6.12.28 , < 6.13 (semver)
Affected: 6.14.6 , < 6.15 (semver)
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Linux Linux Affected: 6.15
Unaffected: 0 , < 6.15 (semver)
Unaffected: 7.1.8 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/bluetooth/hci_sync.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "c53c70ec289ee12f20c4f1b2fbfd151762c01f67",
              "status": "affected",
              "version": "6d0417e4e1cf66fd917f06f0454958362714ef7d",
              "versionType": "git"
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              "versionType": "git"
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              "versionType": "semver"
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          "product": "Linux",
          "programFiles": [
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          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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              "status": "affected",
              "version": "6.15"
            },
            {
              "lessThan": "6.15",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
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              "status": "unaffected",
              "version": "7.1.8",
              "versionType": "semver"
            },
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              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
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        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
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                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.8",
                  "versionStartIncluding": "6.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.12.28",
                  "vulnerable": true
                },
                {
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                  "versionStartIncluding": "6.14.6",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_sync: hold conn in hci_connect_pa_sync() callback\n\nThere is theoretical UAF if the conn is freed while the hci_sync task is\nrunning.\n\nHold refcount to avoid that."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - Reached only via local AF_BLUETOOTH BTPROTO_ISO SOCK_SEQPACKET listen() for LE broadcast PA sync (iso_listen_bis\u2192hci_pa_create_sync\u2192hci_connect_pa_sync); no over-the-air packet parsing triggers the bug and a remote Bluetooth peer alone cannot invoke it.\nAC:L - Use-after-free race is attacker-controlled: a local process can listen() to start hci_le_pa_create_sync and immediately close/unlink the socket to drop the PA_LINK hci_conn while cmd_sync_work is still running, retrying until the callback dereferences freed memory.\nPR:L - ISO sockets perform no capability checks in iso_sock_create/bt_sock_create (only init_net), so any unprivileged local user who can open AF_BLUETOOTH sockets on a BT_ISO-capable host can reach hci_connect_pa_sync without CAP_NET_ADMIN or root.\nUI:N - Exploitation requires no victim action; the attacker opens, binds, and listens on their own ISO socket and races teardown\u2014typical on phones/headsets running LE Audio broadcast receivers with Bluetooth access granted to the attacking app/process.\nS:U - Impact stays within kernel memory via hci_conn UAF in create_pa_complete/hci_le_pa_create_sync; this is standard kernel memory corruption/privilege escalation, not a cross-boundary escape (VM, IOMMU, or sandbox).\nC:H - UAF of struct hci_conn lets an attacker influence freed slab contents and read adjacent kernel data through hci_conn_valid(), conn-\u003eflags, and conn-\u003eiso_qos dereferences during async PA sync work and error callbacks.\nI:H - Freed hci_conn is written via set_bit/clear_bit on conn-\u003eflags and error-path hci_connect_cfm()/hci_conn_add_unset in create_pa_complete; heap grooming of the reclaimed allocation enables arbitrary kernel writes and control-flow hijack.\nA:H - Dereferencing or deleting a freed hci_conn in hci_cmd_sync_work reliably causes kernel memory corruption, oops, or panic; UAFs in this subsystem have been observed to crash the host even when not fully exploited for privilege escalation."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:48:18.894Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/c53c70ec289ee12f20c4f1b2fbfd151762c01f67"
        },
        {
          "url": "https://git.kernel.org/stable/c/44fc74069d8988f2825246f9401218e29de2c0ab"
        }
      ],
      "title": "Bluetooth: hci_sync: hold conn in hci_connect_pa_sync() callback",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74529",
    "datePublished": "2026-08-15T12:27:44.783Z",
    "dateReserved": "2026-08-15T05:44:03.912Z",
    "dateUpdated": "2026-08-17T05:48:18.894Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74529",
      "date": "2026-09-05",
      "epss": "0.0012",
      "percentile": "0.02079"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74529\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T13:17:58.190\",\"lastModified\":\"2026-08-17T06:19:49.770\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nBluetooth: hci_sync: hold conn in hci_connect_pa_sync() callback\\n\\nThere is theoretical UAF if the conn is freed while the hci_sync task is\\nrunning.\\n\\nHold refcount to avoid that.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/bluetooth/hci_sync.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6d0417e4e1cf66fd917f06f0454958362714ef7d\",\"lessThan\":\"c53c70ec289ee12f20c4f1b2fbfd151762c01f67\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6d0417e4e1cf66fd917f06f0454958362714ef7d\",\"lessThan\":\"44fc74069d8988f2825246f9401218e29de2c0ab\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"eb8b860e87b296bd1874c79a668081efd00f9754\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"94bf6380e936339a700c0b3171a49baf512aa70b\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6.12.28\",\"lessThan\":\"6.13\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.14.6\",\"lessThan\":\"6.15\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/bluetooth/hci_sync.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.15\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.15\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.8\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/44fc74069d8988f2825246f9401218e29de2c0ab\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c53c70ec289ee12f20c4f1b2fbfd151762c01f67\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-17T14:55:56+00:00",
      "cve": "CVE-2026-74529",
      "id": "CVE-2026-74529",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Bluetooth: hci_sync: hold conn in hci_connect_pa_sync() callback",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74529.json",
      "version": "3"
    }
  }
}



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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

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.


Detection rules are retrieved from Rulezet.