SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-19417

The allocated buffer can fit only MQTT_MAX_TOPIC_LENGTH (default 64) bytes, and a length check is missing.

CRITICAL 10.0EPSS 5.69%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (5.69%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

An issue was discovered in the MQTT server in Contiki-NG before 4.2. The function parse_publish_vhdr() that parses MQTT PUBLISH messages with a variable length header uses memcpy to input data into a fixed size buffer. The allocated buffer can fit only MQTT_MAX_TOPIC_LENGTH (default 64) bytes, and a length check is missing. This could lead to Remote Code Execution via a stack-smashing attack (overwriting the function return address). Contiki-NG does not separate the MQTT server from other servers and the OS modules, so access to all memory regions is possible.

CVSS 3.0
10.0 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS
5.69% probability · 93th percentile
CISA KEV
Not listed
Weakness
CWE-119
Affected
contiki-ng/contiki-ng
Source
cve@mitre.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.