Log in Start free

Vulnerability · Published Jun 18, 2020 · Assigned by mitre

CVE-2020-12887

High 7.5

In plain English

A high-severity security flaw in the affected software. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.7% (higher than 78% of all known vulnerabilities).

Severity (CVSS NVD)7.5High
Exploit odds (30 days)1.7%top 22.3% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

VendorProductVersions
n/a n/a n/a

References