CVE-2020-12887
Severity CVSS v4.0:
Pending analysis
Type:
CWE-190
Integer Overflow or Wraparound
Publication date:
18/06/2020
Last modified:
21/07/2021
Description
Memory leaks were discovered in the CoAP library in Arm Mbed OS 5.15.3 when using the Arm mbed-coap library 5.1.5. The CoAP parser is responsible for parsing received CoAP packets. The function sn_coap_parser_options_parse() parses the CoAP option number field of all options present in the input packet. Each option number is calculated as a sum of the previous option number and a delta of the current option. The delta and the previous option number are expressed as unsigned 16-bit integers. Due to lack of overflow detection, it is possible to craft a packet that wraps the option number around and results in the same option number being processed again in a single packet. Certain options allocate memory by calling a memory allocation function. In the cases of COAP_OPTION_URI_QUERY, COAP_OPTION_URI_PATH, COAP_OPTION_LOCATION_QUERY, and COAP_OPTION_ETAG, there is no check on whether memory has already been allocated, which in conjunction with the option number integer overflow may lead to multiple assignments of allocated memory to a single pointer. This has been demonstrated to lead to memory leak by buffer orphaning. As a result, the memory is never freed.
Impact
Base Score 3.x
7.50
Severity 3.x
HIGH
Base Score 2.0
5.00
Severity 2.0
MEDIUM
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:arm:mbed-coap:5.1.5:*:*:*:*:*:*:* | ||
| cpe:2.3:o:arm:mbed_os:5.15.3:*:*:*:*:*:*:* |
To consult the complete list of CPE names with products and versions, see this page