What is CVE-2018-19587?

CVE-2018-19587 is a medium-severity vulnerability in Cesanta Mongoose, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 6.5/10. Published 2018-11-27.

How severe is CVE-2018-19587?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Buffer overflow in Cesanta Mongoose

CVE-2018-19587

In Cesanta Mongoose 6.13, a SIGSEGV exists in the mongoose.c mg_mqtt_add_session() function.

Vulnerability class: Buffer Overflow

Published 2018-11-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.009 (59.6th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 59.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Cesanta Mongoose — versions 6.13

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

References

github.com/insi2304/mongoose-fuzz (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2018-19587?: CVE-2018-19587 is a medium-severity vulnerability in Cesanta Mongoose, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 6.5/10. Published 2018-11-27.
How severe is CVE-2018-19587?: Medium severity. CVSS v3 base score is 6.5 out of 10.