CVE-2018-18765

Severity: critical (CVSS 9.1 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-10-29 · updated 2026-06-17
Weakness: CWE-125

Description

An exploitable arbitrary memory read vulnerability exists in the MQTT packet-parsing functionality of Cesanta Mongoose 6.13. It is a heap-based buffer over-read in mg_mqtt_next_subscribe_topic. A specially crafted MQTT SUBSCRIBE packet can cause an arbitrary out-of-bounds memory read potentially resulting in information disclosure and denial of service. An attacker needs to send a specially crafted MQTT packet over the network to trigger this vulnerability.

Affected products

Cesanta Mongoose: 6.13

References

https://github.com/TiffanyBlue/PoCbyMyself/blob/master/mongoose6.13/mqtt/Cesanta%20Mongoose%20MQTT%20mg_mqtt_next_subscribe_topic%20heap%20buffer%20overflow.md
https://twitter.com/thracky/status/1059472674940993541
https://github.com/TiffanyBlue/PoCbyMyself/blob/master/mongoose6.13/mqtt/Cesanta%20Mongoose%20MQTT%20mg_mqtt_next_subscribe_topic%20heap%20buffer%20overflow.md
https://twitter.com/thracky/status/1059472674940993541

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