CVE-2026-98737
Status: ReceivedUnscored—
Severity—Unscored
Exploitation probability0.20 %higher than 9% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_sync: Fix inquiry cache use-after-free
The sync command worker holds hdev->req_lock, but inquiry-cache updates and flushes use hdev->lock. Both hci_acl_create_conn_sync() and hci_stop_discovery_sync() look up entries and read their fields without taking hdev->lock.
After either lookup returns, a concurrent HCIINQUIRY ioctl can acquire hdev->lock and flush the cache, freeing the entry. The worker then reads the freed entry while preparing a create-connection or remote-name-cancel command. The list traversal also races with cache updates and removal.
Read full descriptionShow less
Hold hdev->lock across each lookup and all reads from its result. Copy the remote address before unlocking so discovery cancellation does not retain a cache entry pointer. Release the lock before sending synchronous HCI commands, since their completion handlers may need the same lock.
Technical details traces, logs and code from the original report
KASAN reported these accesses: BUG: KASAN: slab-use-after-free in hci_acl_create_conn_sync+0x5f1/0x650 Workqueue: hci0 hci_cmd_sync_work Call Trace: hci_acl_create_conn_sync+0x5f1/0x650 hci_cmd_sync_work+0x13c/0x290 Allocated by task 90: hci_inquiry_cache_update+0x3e6/0x7d0 hci_inquiry_result_evt+0x3cb/0x560 Freed by task 93: hci_inquiry_cache_flush+0x111/0x2b0 hci_inquiry+0x2f2/0x780 hci_sock_ioctl+0x269/0x5f0 BUG: KASAN: slab-use-after-free in hci_stop_discovery_sync+0x3b1/0x3c0 Workqueue: hci0 hci_cmd_sync_work Call Trace: hci_stop_discovery_sync+0x3b1/0x3c0 hci_cmd_sync_work+0x173/0x300 Allocated by task 86: hci_inquiry_cache_update+0x483/0x940 hci_inquiry_result_evt+0x3cb/0x560 Freed by task 91: hci_inquiry_cache_flush+0x13e/0x2f0 hci_inquiry+0x2f2/0x780 hci_sock_ioctl+0x269/0x5f0
CVSS
NVD hasn't assigned a CVSS score to this CVE (common since the April 2026 policy change).
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days
- 0.20 %
- Percentile among all scored CVEs
- 9
- Score date
- 10/20/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
References
Show 4 references
Raw JSON (NVD)
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{
"id": "CVE-2026-98737",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "cf75ad8b41d2aa06f98f365d42a3ae8b059daddd",
"lessThan": "52edf1c0e59dea37b8368c4a2559dca96b2fdfea",
"versionType": "git"
},
{
"status": "affected",
"version": "cf75ad8b41d2aa06f98f365d42a3ae8b059daddd",
"lessThan": "333257e6e4a7bcaaea82fd357121d0f1e6b76c7b",
"versionType": "git"
},
{
"status": "affected",
"version": "cf75ad8b41d2aa06f98f365d42a3ae8b059daddd",
"lessThan": "a642f498f0b08f2aa9f4a69468db92f57a72349d",
"versionType": "git"
},
{
"status": "affected",
"version": "cf75ad8b41d2aa06f98f365d42a3ae8b059daddd",
"lessThan": "8ed67535fdff40ca652bcd4ac7da68d11d01bd34",
"versionType": "git"
}
],
"programFiles": [
"net/bluetooth/hci_sync.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.17"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.17",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.56",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/bluetooth/hci_sync.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-10-18T16:17:27.370",
"references": [
{
"url": "https://git.kernel.org/stable/c/333257e6e4a7bcaaea82fd357121d0f1e6b76c7b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/52edf1c0e59dea37b8368c4a2559dca96b2fdfea",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8ed67535fdff40ca652bcd4ac7da68d11d01bd34",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a642f498f0b08f2aa9f4a69468db92f57a72349d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_sync: Fix inquiry cache use-after-free\n\nThe sync command worker holds hdev->req_lock, but inquiry-cache updates\nand flushes use hdev->lock. Both hci_acl_create_conn_sync() and\nhci_stop_discovery_sync() look up entries and read their fields without\ntaking hdev->lock.\n\nAfter either lookup returns, a concurrent HCIINQUIRY ioctl can acquire\nhdev->lock and flush the cache, freeing the entry. The worker then reads\nthe freed entry while preparing a create-connection or remote-name-cancel\ncommand. The list traversal also races with cache updates and removal.\n\nKASAN reported these accesses:\n\n BUG: KASAN: slab-use-after-free in hci_acl_create_conn_sync+0x5f1/0x650\n Workqueue: hci0 hci_cmd_sync_work\n Call Trace:\n hci_acl_create_conn_sync+0x5f1/0x650\n hci_cmd_sync_work+0x13c/0x290\n\n Allocated by task 90:\n hci_inquiry_cache_update+0x3e6/0x7d0\n hci_inquiry_result_evt+0x3cb/0x560\n\n Freed by task 93:\n hci_inquiry_cache_flush+0x111/0x2b0\n hci_inquiry+0x2f2/0x780\n hci_sock_ioctl+0x269/0x5f0\n\n BUG: KASAN: slab-use-after-free in hci_stop_discovery_sync+0x3b1/0x3c0\n Workqueue: hci0 hci_cmd_sync_work\n Call Trace:\n hci_stop_discovery_sync+0x3b1/0x3c0\n hci_cmd_sync_work+0x173/0x300\n\n Allocated by task 86:\n hci_inquiry_cache_update+0x483/0x940\n hci_inquiry_result_evt+0x3cb/0x560\n\n Freed by task 91:\n hci_inquiry_cache_flush+0x13e/0x2f0\n hci_inquiry+0x2f2/0x780\n hci_sock_ioctl+0x269/0x5f0\n\nHold hdev->lock across each lookup and all reads from its result. Copy the\nremote address before unlocking so discovery cancellation does not retain\na cache entry pointer. Release the lock before sending synchronous HCI\ncommands, since their completion handlers may need the same lock."
}
],
"lastModified": "2026-10-19T10:19:37.850",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}