Bluetooth: RFCOMM: serialize security confirmation handling
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: serialize security confirmation handling rfcomm_security_cfm() looks up a session on session_list and then walks its DLC list without holding rfcomm_mutex. Since RFCOMM session teardown uses rfcomm_mutex, krfcommd can close and free the same session and DLCs concurrently: hci_rx_work krfcommd ----------- --------- rfcomm_session_get() rfcomm_lock() rfcomm_session_close() rfcomm_dlc_unlink() rfcomm_session_del() kfree(s) rfcomm_unlock() walk s->dlcs The callback can then read a freed session list head and touch freed DLCs while updating their flags or timers. Serialize the session lookup and DLC traversal in rfcomm_security_cfm() with rfcomm_mutex. This matches the existing RFCOMM session lifetime rules and prevents concurrent rfcomm_session_del() / rfcomm_dlc_unlink() from tearing the objects down while the callback is using them. KASAN reported: BUG: KASAN: slab-use-after-free in rfcomm_security_cfm+0x41c/0x440 Read of size 8 at addr ffff888111fb3960 by task kworker/u17:1/89 Workqueue: hci0 hci_rx_work Call Trace: rfcomm_security_cfm+0x41c/0x440 hci_encrypt_cfm+0x139/0x590 hci_encrypt_change_evt+0x37b/0xc40 hci_event_packet+0x71b/0xb20 hci_rx_work+0x293/0x730 Allocated by task 69: rfcomm_session_add+0x9e/0x2f0 rfcomm_run+0x44b/0x41e0 Freed by task 69: kfree+0x131/0x3c0 rfcomm_session_del+0x188/0x220 rfcomm_run+0x1985/0x41e0
CVE-2026-89569
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-2026-89569
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": "08c30aca9e698faddebd34f81e1196295f9dc063",
"lessThan": "62ce8b33eb238cf18c15207332fbdc26d858f592",
"versionType": "git"
},
{
"status": "affected",
"version": "08c30aca9e698faddebd34f81e1196295f9dc063",
"lessThan": "3873f3449701b3dc98cba577923be6493598e7a1",
"versionType": "git"
},
{
"status": "affected",
"version": "08c30aca9e698faddebd34f81e1196295f9dc063",
"lessThan": "7ded3264106418c6456ccceaafd9fda596ce12c3",
"versionType": "git"
},
{
"status": "affected",
"version": "08c30aca9e698faddebd34f81e1196295f9dc063",
"lessThan": "82425b14f0fb22e46cfddc56d6465570f5ed0ce6",
"versionType": "git"
},
{
"status": "affected",
"version": "08c30aca9e698faddebd34f81e1196295f9dc063",
"lessThan": "1b7841ffad08e911e8c4b9470f3fa08423568940",
"versionType": "git"
},
{
"status": "affected",
"version": "08c30aca9e698faddebd34f81e1196295f9dc063",
"lessThan": "946d76db77ee5f922968ce558629ae47b381e3fc",
"versionType": "git"
},
{
"status": "affected",
"version": "08c30aca9e698faddebd34f81e1196295f9dc063",
"lessThan": "fbf7961964a6e93360179f64712320ae9a1e9577",
"versionType": "git"
},
{
"status": "affected",
"version": "08c30aca9e698faddebd34f81e1196295f9dc063",
"lessThan": "759c185d0bbdb131357408f50b8735e04ed3caff",
"versionType": "git"
}
],
"programFiles": [
"net/bluetooth/rfcomm/core.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.10"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.10",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.270",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.221",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.109",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/bluetooth/rfcomm/core.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89569
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #35080 · Revision 1
- Added to Heist Feed
- Publisher date