cbcvebase.
CVE-2024-26903
published 2024-04-17

CVE-2024-26903: In the Linux kernel, the following vulnerability has been resolved: Bluetooth: rfcomm: Fix null-ptr-deref in rfcomm_check_security During our fuzz testing of…

PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.28%
20.1th percentile
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: rfcomm: Fix null-ptr-deref in rfcomm_check_security During our fuzz testing of the connection and disconnection process at the RFCOMM layer, we discovered this bug. By comparing the packets from a normal connection and disconnection process with the testcase that triggered a KASAN report. We analyzed the cause of this bug as follows: 1. In the packets captured during a normal connection, the host sends a `Read Encryption Key Size` type of `HCI_CMD` packet (Command Opcode: 0x1408) to the controller to inquire the length of encryption key.After receiving this packet, the controller immediately replies with a Command Completepacket (Event Code: 0x0e) to return the Encryption Key Size. 2. In our fuzz test case, the timing of the controller's response to this packet was delayed to an unexpected point: after the RFCOMM and L2CAP layers had disconnected but before the HCI layer had disconnected. 3. After receiving the Encryption Key Size Response at the time described in point 2, the host still called the rfcomm_check_security function. However, by this time `struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;` had already been released, and when the function executed `return hci_conn_security(conn->hcon, d->sec_level, auth_type, d->out);`, specifically when accessing `conn->hcon`, a null-ptr-deref error occurred. To fix this bug, check if `sk->sk_state` is BT_CLOSED before calling rfcomm_recv_frame in rfcomm_process_rx.

Affected

29 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.82-1 (bookworm)linux 6.1.82-1 (bookworm)
linuxlinux
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 369f419c097e82407dd429a202cde9a73d3ae29b369f419c097e82407dd429a202cde9a73d3ae29b
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 5f369efd9d963c1f711a06c9b8baf9f5ce616d855f369efd9d963c1f711a06c9b8baf9f5ce616d85
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 81d7d920a22fd58ef9aedb1bd0a68ee32bd23e9681d7d920a22fd58ef9aedb1bd0a68ee32bd23e96
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8d1753973f598531baaa2c1033cf7f7b5bb004b08d1753973f598531baaa2c1033cf7f7b5bb004b0
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 567c0411dc3b424fc7bd1e6109726d7ba32d4f73567c0411dc3b424fc7bd1e6109726d7ba32d4f73
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3ead59bafad05f2967ae2438c0528d53244cfde53ead59bafad05f2967ae2438c0528d53244cfde5
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 5f9fe302dd3a9bbc50f4888464c1773f45166bfd5f9fe302dd3a9bbc50f4888464c1773f45166bfd
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2535b848fa0f42ddff3e5255cf5e742c9b77bb262535b848fa0f42ddff3e5255cf5e742c9b77bb26
linuxlinux_kernel< 4.19.3114.19.311
linuxlinux_kernel>= 0 < 5.10.216-15.10.216-1
linuxlinux_kernel>= 0 < 6.1.82-16.1.82-1
linuxlinux_kernel>= 0 < 6.7.12-16.7.12-1
linuxlinux_kernel>= 0 < 6.7.12-16.7.12-1
linuxlinux_kernel>= 0 < 5.4.0-189.2095.4.0-189.209
linuxlinux_kernel>= 0 < 5.15.0-112.1225.15.0-112.122
linuxlinux_kernel>= 0 < 4.4.0-258.2924.4.0-258.292
linuxlinux_kernel>= 0 < 4.15.0-228.2404.15.0-228.240
linuxlinux_kernel>= 4.20 < 5.4.2735.4.273
linuxlinux_kernel>= 5.11 < 5.15.1535.15.153
linuxlinux_kernel>= 5.16 < 6.1.836.1.83
linuxlinux_kernel>= 5.5 < 5.10.2145.10.214
linuxlinux_kernel>= 6.2 < 6.6.236.6.23
linuxlinux_kernel>= 6.7 < 6.7.116.7.11

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv7.0HIGH
vendor_ubuntu7.0HIGH
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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