CVE-2018-20356: Cesanta Mongoose

Critical severity, CVSS 9.8. EPSS: 3.6% chance of exploitation in the next 30 days.

An invalid read of 8 bytes due to a use-after-free vulnerability in the mg_http_free_proto_data_cgi function call in mongoose.c in Cesanta Mongoose Embedded Web Server Library 6.13 and earlier allows a denial of service (application crash) or remote code execution.

Affected products

• Cesanta Mongoose: up to and including 6.13

Published 2019-06-10. Last modified 2026-06-17.