CVE-2021-42755

mediumpriority · track · 17EPSS 0.004 · 34 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.40% (34th) EPSS

CVSS 4.3 · medium

Is it mine?

131 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

An integer overflow / wraparound vulnerability [CWE-190] in FortiSwitch 7.0.2 and below, 6.4.9 and below, 6.2.x, 6.0.x; FortiRecorder 6.4.2 and below, 6.0.10 and below; FortiOS 7.0.2 and below, 6.4.8 and below, 6.2.10 and below, 6.0.x; FortiProxy 7.0.0, 2.0.6 and below, 1.2.x, 1.1.x, 1.0.x; FortiVoiceEnterprise 6.4.3 and below, 6.0.10 and below dhcpd daemon may allow an unauthenticated and network adjacent attacker to crash the dhcpd deamon, resulting in potential denial of service.

cvss

Technical severity, 0–10. One row per scoring source.

4.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.14.3mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lprimary · NVD / NIST USexploitability 2.8 · impact 1.4

v3.14.3mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:F/RL:U/RC:Csecondary · ENISA EU

v3.14.3mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · psirt@fortinet.comexploitability 2.8 · impact 1.4

v3.14mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-190USprimary

affected products (131)

Products and version ranges known to be affected.

Fortinet Fortinet FortiSwitch, FortiRecorder, FortiVoiceEnterprise, FortiOS, FortiProxy≤ FortiSwitch 7.0.2 and below, 6.4.9 and below, 6.2.x, 6.0.x; FortiRecorder 6.4.2 and below, 6.0.10 and below; FortiOS 7.0.2 and below, 6.4.8 and below, 6.2.10 and below, 6.0.x; FortiProxy 7.0.0, 2.0.6 and below, 1.2.x, 1.1.x, 1.0.x; FortiVoiceEnterprise 6.4.3 and below, 6.0.10 and belowenisa_euvdEU
fortinet fortios= 5.4.0nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.1nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.10nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.11nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.12nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.13nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.2nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.3nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.4nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.5nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.6nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.7nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.8nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.4.9nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.6.0nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.6.1nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.6.10nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.6.11nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 5.6.12nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*

showing 20 of 131

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2022-07-18modified 2026-06-17

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+4644 more

references (8)

External citations — patches, advisories, analysis.

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