CVE-2020-12884
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_multiple_options() parses CoAP options that may occur multiple consecutive times in a single packet. While processing the options, packet_data_pptr is accessed after being incremented by option_len without a prior out-of-bounds memory check.
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The temp_parsed_uri_query_ptr is validated for a correct range, but the range valid for temp_parsed_uri_query_ptr is derived from the amount of allocated heap memory, not the actual input size. Therefore the check of temp_parsed_uri_query_ptr may be insufficient for safe access to the area pointed to by packet_data_pptr. As a result, access to a memory area outside of the intended boundary of the packet buffer is made.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- Puntuación base: 9.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.35%
- Percentil entre todas las CVEs puntuadas: 71
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-125
Referencias
JSON original (NVD)
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"published": "2020-06-18T19:15:09.973",
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"value": "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_multiple_options() parses CoAP options that may occur multiple consecutive times in a single packet. While processing the options, packet_data_pptr is accessed after being incremented by option_len without a prior out-of-bounds memory check. The temp_parsed_uri_query_ptr is validated for a correct range, but the range valid for temp_parsed_uri_query_ptr is derived from the amount of allocated heap memory, not the actual input size. Therefore the check of temp_parsed_uri_query_ptr may be insufficient for safe access to the area pointed to by packet_data_pptr. As a result, access to a memory area outside of the intended boundary of the packet buffer is made."
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"value": "Se detectó una lectura excesiva del búfer en la biblioteca CoAP en Arm Mbed OS versión 5.15.3. El analizador CoAP es responsable de analizar los paquetes CoAP recibidos. La función sn_coap_parser_options_parse_multiple_options() analiza las opciones de CoAP que pueden presentarse varias veces consecutivas en un solo paquete. Mientras se procesan las opciones, se accede a packet_data_pptr después de ser incrementado por option_len sin una comprobación previa de memoria fuera de límites. Temp_parsed_uri_query_ptr es comprobada para un rango correcto, pero el rango válido para temp_parsed_uri_query_ptr es derivado de la cantidad de memoria de pila asignada, no del tamaño de entrada real. Por lo tanto, la comprobación de temp_parsed_uri_query_ptr puede ser insuficiente para un acceso seguro al área señalada por packet_data_pptr. Como resultado, se realiza el acceso a un área de memoria fuera del límite previsto del búfer de paquetes"
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"lastModified": "2026-06-17T02:52:29.060",
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