Out-of-bounds Read Affecting PelionIoT/mbed-coap package, versions [,5.1.6)


Severity

Recommended
0.0
critical
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
1.35% (68th percentile)

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  • Snyk IDSNYK-UNMANAGED-PELIONIOTMBEDCOAP-15323763
  • published20 Feb 2026
  • disclosed18 Jun 2020
  • creditUnknown

Introduced: 18 Jun 2020

CVE-2020-12886  (opens in a new tab)
CWE-125  (opens in a new tab)

How to fix?

Upgrade PelionIoT/mbed-coap to version 5.1.6 or higher.

Overview

Affected versions of this package are vulnerable to Out-of-bounds Read. A buffer over-read was discovered in the CoAP library in Arm Mbed OS 5.15.3. The CoAP parser is responsible for parsing received CoAP packets. The function sn_coap_parser_options_parse() parses the CoAP packet header starting from the message token. The length of the token in the received message is provided in the first byte parsed by the sn_coap_parser_options_parse() function. The length encoded in the message is not validated against the actual input buffer length before accessing the token. As a result, memory access outside of the intended boundary of the buffer may occur.

CVSS Base Scores

version 3.1