Skip to content
Fencer Vulns
critical 9.8

CVE-2019-12951 json

An issue was discovered in Mongoose before 6.15.

published 2019-06-24 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-4526

cvss
9.8
version 3.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.0%
EPSS 2.0% chance of exploitation in 30 days, percentile 80%
public exploits
0
none known

Summary

An issue was discovered in Mongoose before 6.15. The parse_mqtt() function in mg_mqtt.c has a critical heap-based buffer overflow.

Patch / fix

  • cesanta mongoose 6.15
  • swupdate Debian 14, Debian 13, Debian 12 2021.04-1

debian advisories DEBIAN-CVE-2019-12951

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2019-12951 updated cvss 6.5

mongoose: heap-based buffer overflow in parse_mqtt() in mg_mqtt.c

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.95% chance of exploitation in the next 30 days, higher than 80% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.0 9.8 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.