CVE record · CVE-2021-36193

Stack-based buffer overflow in Fortinet FortiFone and others

CVSS 6.3 MediumEPSS 0.0082 · 57th percentile

Published by the CVE Program (CNA: fortinet) at 2 Feb 2022, 11:19 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
Fortinet	FortiFone	affected 3.0.0 to 3.0.11, inclusive semver Other versions: unaffected
Fortinet	FortiADC	affected 7.0.0 affected 6.2.0 to 6.2.2, inclusive semver affected 6.1.0 to 6.1.6, inclusive semver affected 6.0.0 to 6.0.4, inclusive semver affected 5.4.0 to 5.4.5, inclusive semver affected 5.3.0 to 5.3.7, inclusive semver affected 5.2.0 to 5.2.8, inclusive semver affected 5.1.0 to 5.1.7, inclusive semver affected 5.0.0 to 5.0.4, inclusive semver Other versions: unaffected
Fortinet	FortiMail	affected 7.0.0 to 7.0.2, inclusive semver affected 6.4.0 to 6.4.6, inclusive semver affected 6.2.0 to 6.2.8, inclusive semver affected 6.0.0 to 6.0.12, inclusive semver affected 5.4.0 to 5.4.12, inclusive semver Other versions: unaffected
Fortinet	FortiDDoS	affected 5.7.0 affected 5.6.0 to 5.6.1, inclusive semver affected 5.5.0 to 5.5.1, inclusive semver affected 5.4.0 to 5.4.3, inclusive semver affected 5.3.0 to 5.3.2, inclusive semver affected 5.2.0 affected 5.1.0 affected 5.0.0 affected 4.7.0 affected 4.6.0 affected 4.5.0 affected 4.4.0 to 4.4.2, inclusive semver Other versions: unaffected
Fortinet	FortiDDoS-F	affected 6.3.0 affected 6.2.0 to 6.2.2, inclusive semver affected 6.1.0 to 6.1.4, inclusive semver Other versions: unaffected
Fortinet	FortiVoice	affected 6.4.0 to 6.4.4, inclusive semver affected 6.0.0 to 6.0.10, inclusive semver Other versions: unaffected
Fortinet	FortiDDoS-CM	affected 5.5.0 to 5.5.1, inclusive semver affected 5.4.0 to 5.4.3, inclusive semver affected 5.3.0 to 5.3.1, inclusive semver affected 5.2.0 affected 5.1.0 affected 5.0.0 affected 4.7.0 Other versions: unaffected
Fortinet	FortiWeb	affected 6.4.0 to 6.4.1, inclusive semver affected 6.3.0 to 6.3.15, inclusive semver Other versions: unaffected
Fortinet	FortiRecorder	affected 6.4.0 to 6.4.2, inclusive semver affected 6.0.0 to 6.0.10, inclusive semver affected 2.7.0 to 2.7.7, inclusive semver affected 2.6.0 to 2.6.3, inclusive semver Other versions: unaffected
Fortinet	FortiNDR	affected 1.5.0 to 1.5.3, inclusive semver affected 1.4.0 affected 1.3.0 to 1.3.1, inclusive semver affected 1.2.0 affected 1.1.0 Other versions: unaffected

Identifiers: CVE-2021-36193
CNA: fortinet
Weakness (CWE): CWE-121
Tags: Fortinet FortiFone
Fortinet FortiADC
Fortinet FortiMail
Fortinet FortiDDoS
Fortinet FortiDDoS-F
Fortinet FortiVoice
Fortinet FortiDDoS-CM
Fortinet FortiWeb
Memory corruption
Published: 2 Feb 2022
Updated: 13 Jan 2026

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.3	Medium	3.1	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:U/RC:C	CNA (fortinet)

CISA KEV Not listed.
EPSS 0.0082, the 57th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the CVE Program, published 2 Feb 2022. New records show when each source confirmed them.

Sources

References from the CNA

fortiguard.com/advisory/FG-IR-21-132

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.