Описание
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req
Syzbot reported a KASAN stack-out-of-bounds read in l2cap_build_cmd() that is triggered by a malformed Enhanced Credit Based Connection Request.
The vulnerability stems from l2cap_ecred_conn_req(). The function allocates
a local stack buffer (pdu) designed to hold a maximum of 5 Source Channel
IDs (SCIDs), totaling 18 bytes. When an attacker sends a request with more
than 5 SCIDs, the function calculates rsp_len based on this unvalidated
cmd_len before checking if the number of SCIDs exceeds
L2CAP_ECRED_MAX_CID.
If the SCID count is too high, the function correctly jumps to the
response label to reject the packet, but rsp_len retains the
attacker's oversized value. Consequently, l2cap_send_cmd() is instructed
to read past the end of the 18-byte pdu buffer, triggering a
KASAN panic.
Fix this by moving the assignment of rsp_len t...
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req
Syzbot reported a KASAN stack-out-of-bounds read in l2cap_build_cmd() that is triggered by a malformed Enhanced Credit Based Connection Request.
The vulnerability stems from l2cap_ecred_conn_req(). The function allocates
a local stack buffer (pdu) designed to hold a maximum of 5 Source Channel
IDs (SCIDs), totaling 18 bytes. When an attacker sends a request with more
than 5 SCIDs, the function calculates rsp_len based on this unvalidated
cmd_len before checking if the number of SCIDs exceeds
L2CAP_ECRED_MAX_CID.
If the SCID count is too high, the function correctly jumps to the
response label to reject the packet, but rsp_len retains the
attacker's oversized value. Consequently, l2cap_send_cmd() is instructed
to read past the end of the 18-byte pdu buffer, triggering a
KASAN panic.
Fix this by moving the assignment of rsp_len to after the num_scid
boundary check. If the packet is rejected, rsp_len will safely
remain 0, and the error response will only read the 8-byte base header
from the stack.
Ссылки
- https://nvd.nist.gov/vuln/detail/CVE-2026-31513
- https://git.kernel.org/stable/c/5b35f8211a913cfe7ab9d54fa36a272d2059a588
- https://git.kernel.org/stable/c/9d87cb22195b2c67405f5485d525190747ad5493
- https://git.kernel.org/stable/c/a3d9c50d69785ae02e153f000da1b5fd6dbfdf1b
- https://git.kernel.org/stable/c/c8e1a27edb8b4e5afb56b384acd7b6c2dec1b7cc
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req Syzbot reported a KASAN stack-out-of-bounds read in l2cap_build_cmd() that is triggered by a malformed Enhanced Credit Based Connection Request. The vulnerability stems from l2cap_ecred_conn_req(). The function allocates a local stack buffer (`pdu`) designed to hold a maximum of 5 Source Channel IDs (SCIDs), totaling 18 bytes. When an attacker sends a request with more than 5 SCIDs, the function calculates `rsp_len` based on this unvalidated `cmd_len` before checking if the number of SCIDs exceeds L2CAP_ECRED_MAX_CID. If the SCID count is too high, the function correctly jumps to the `response` label to reject the packet, but `rsp_len` retains the attacker's oversized value. Consequently, l2cap_send_cmd() is instructed to read past the end of the 18-byte `pdu` buffer, triggering a KASAN panic. Fix this by moving the assignment of `rsp_len` to aft...
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req Syzbot reported a KASAN stack-out-of-bounds read in l2cap_build_cmd() that is triggered by a malformed Enhanced Credit Based Connection Request. The vulnerability stems from l2cap_ecred_conn_req(). The function allocates a local stack buffer (`pdu`) designed to hold a maximum of 5 Source Channel IDs (SCIDs), totaling 18 bytes. When an attacker sends a request with more than 5 SCIDs, the function calculates `rsp_len` based on this unvalidated `cmd_len` before checking if the number of SCIDs exceeds L2CAP_ECRED_MAX_CID. If the SCID count is too high, the function correctly jumps to the `response` label to reject the packet, but `rsp_len` retains the attacker's oversized value. Consequently, l2cap_send_cmd() is instructed to read past the end of the 18-byte `pdu` buffer, triggering a KASAN panic. Fix this by moving the assignment of `rsp_len` to aft...
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req Syzbot reported a KASAN stack-out-of-bounds read in l2cap_build_cmd() that is triggered by a malformed Enhanced Credit Based Connection Request. The vulnerability stems from l2cap_ecred_conn_req(). The function allocates a local stack buffer (`pdu`) designed to hold a maximum of 5 Source Channel IDs (SCIDs), totaling 18 bytes. When an attacker sends a request with more than 5 SCIDs, the function calculates `rsp_len` based on this unvalidated `cmd_len` before checking if the number of SCIDs exceeds L2CAP_ECRED_MAX_CID. If the SCID count is too high, the function correctly jumps to the `response` label to reject the packet, but `rsp_len` retains the attacker's oversized value. Consequently, l2cap_send_cmd() is instructed to read past the end of the 18-byte `pdu` buffer, triggering a KASAN panic. Fix this by moving the assignment of `rsp_len` to a
In the Linux kernel, the following vulnerability has been resolved: B ...
