ARM Mbed OS 5.15.3 CoAP Library sn_coap_parser_options_parse memory leak

Summaryinfo

A vulnerability classified as critical has been found in ARM Mbed OS 5.15.3. Affected is the function sn_coap_parser_options_parse of the component CoAP Library. This manipulation causes memory leak. This vulnerability is registered as CVE-2020-12887. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as critical was found in ARM Mbed OS 5.15.3. Affected by this vulnerability is the function sn_coap_parser_options_parse of the component CoAP Library. The manipulation with an unknown input leads to a memory leak vulnerability. The CWE definition for the vulnerability is CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was published 06/18/2020 (GitHub Repository). The advisory is shared at github.com. This vulnerability is known as CVE-2020-12887 since 05/15/2020. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Similar entries are available at VDB-156921, VDB-156922, VDB-156923 and VDB-156924. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

• ARM

Name

• Mbed OS

Version

• 5.15.3

License

• commercial

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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