Bluetooth: SCO: fix race conditions in sco_sock_connect()
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: fix race conditions in sco_sock_connect() sco_sock_connect() checks sk_state and sk_type without holding the socket lock. Two concurrent connect() syscalls on the same socket can both pass the check and enter sco_connect(), leading to use-after-free. The buggy scenario involves three participants and was confirmed with additional logging instrumentation: Thread A (connect): HCI disconnect: Thread B (connect): sco_sock_connect(sk) sco_sock_connect(sk) sk_state==BT_OPEN sk_state==BT_OPEN (pass, no lock) (pass, no lock) sco_connect(sk): sco_connect(sk): hci_dev_lock hci_dev_lock hci_connect_sco <- blocked -> hcon1 sco_conn_add->conn1 lock_sock(sk) sco_chan_add: conn1->sk = sk sk->conn = conn1 sk_state=BT_CONNECT release_sock hci_dev_unlock hci_dev_lock sco_conn_del: lock_sock(sk) sco_chan_del: sk->conn=NULL conn1->sk=NULL sk_state= BT_CLOSED SOCK_ZAPPED release_sock hci_dev_unlock (unblocked) hci_connect_sco -> hcon2 sco_conn_add -> conn2 lock_sock(sk) sco_chan_add: sk->conn=conn2 sk_state= BT_CONNECT // zombie sk! release_sock hci_dev_unlock Thread B revives a BT_CLOSED + SOCK_ZAPPED socket back to BT_CONNECT. Subsequent cleanup triggers double sock_put() and use-after-free. Meanwhile conn1 is leaked as it was orphaned when sco_conn_del() cleared the association. Fix this by: - Moving lock_sock() before the sk_state/sk_type checks in sco_sock_connect() to serialize concurrent connect attempts -
CVE-2026-43023
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-43023
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "70a13b1e25fef37c87c8a1228ddb8900efbca7cf",
"lessThan": "dabf22269242e2f2bf44c43fcdc2fa763df7f9cc",
"versionType": "git"
},
{
"status": "affected",
"version": "9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3",
"lessThan": "adb90cd0f9f7a8d438fcb93354040fbafc5ae2a0",
"versionType": "git"
},
{
"status": "affected",
"version": "9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3",
"lessThan": "7e296ffdab5bdab718dff7c14288fdcb9154fa27",
"versionType": "git"
},
{
"status": "affected",
"version": "9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3",
"lessThan": "98c8d3bfdaa657d8f472dbbebd7ea8cd816d8a8d",
"versionType": "git"
},
{
"status": "affected",
"version": "9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3",
"lessThan": "d002bd11024bd231bcb606877e33951ffb7bed14",
"versionType": "git"
},
{
"status": "affected",
"version": "9a8ec9e8ebb5a7c0cfbce2d6b4a6b67b2b78e8f3",
"lessThan": "8a5b0135d4a5d9683203a3d9a12a711ccec5936b",
"versionType": "git"
},
{
"status": "affected",
"version": "6.1.109",
"lessThan": "6.1.168",
"versionType": "semver"
}
],
"programFiles": [
"net/bluetooth/sco.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.3"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.3",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.168",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.134",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.81",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.22",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.12",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/bluetooth/sco.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-43023
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #40002 · Revision 1
- Added to Heist Feed
- Publisher date