ASA-2019-00013 – Linux: Heap address information leak while using L2CAP_PARSE_CONF_RSP


Allele Security Alert

ASA-2019-00013

Identifier(s)

ASA-2019-00013, CVE-2019-3460

Title

Heap address information leak while using L2CAP_PARSE_CONF_RSP

Vendor(s)

The Linux foundation

Product(s)

Linux kernel

Affected version(s)

Linux kernel since 2.6.12-rc2

Fixed version(s)

Unknown

Proof of concept

Unknown

Description

A flaw was found in the Linux kernels implementation of Logical link control and adaptation protocol (L2CAP), part of the bluetooth stack in the l2cap_parse_conf_rsp, l2cap_parse_conf_req functions.

An attacker with physical access within the range of standard bluetooth transmission can create a specially crafted packet. The response to this specially crafted packet can contain part of the kernel stack which can be used in a further attack.

Technical details

In the functions l2cap_parse_conf_rsp() and l2cap_parse_conf_req() in l2cap_core.c, and other locations, there is a while loop which is used to parse configuration elements during an L2cap connection negotiation process. In this function, the processing of data is performed in the while loop before the check if all the data processed is inside the buffer. In addition, if data outside of the buffer is processed, the function will not return an error. Therefore, data that is out-of-bounds can be processed, and in some cases returned to the attacker.

Credits

Shlomi Oberman, Yuli Shapiro and Karamba Security Ltd. research team

Reference(s)

Linux kernel: Bluetooth: two remote infoleaks (CVE-2019-3459, CVE-2019-3460)
https://seclists.org/oss-sec/2019/q1/58

[PATCH 1/2] Bluetooth: check message types in l2cap_get_conf_opt
https://lore.kernel.org/linux-bluetooth/20190110062833.GA15047@kroah.com/

CVE-2019-3460
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-3460

CVE-2019-3460
https://nvd.nist.gov/vuln/detail/CVE-2019-3460

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Last modified: February 15, 2019

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