CVE-2021-42757

mediumpriority · track · 27EPSS 0.005 · 44 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.52% (44th) EPSS

CVSS 4.6 · medium

Is it mine?

145 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · fstec_bdu

EPSS · scored 2026-10-25

A buffer overflow [CWE-121] in the TFTP client library of FortiOS before 6.4.7 and FortiOS 7.0.0 through 7.0.2, may allow an authenticated local attacker to achieve arbitrary code execution via specially crafted command line arguments.

cvss

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

6.7

010

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

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 3.9 · impact 6.4

v3.16.7mediumCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 0.8 · impact 5.9

v3.16.7mediumAV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.16.3mediumCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:U/RC:Csecondary · ENISA EU

v3.16.7mediumCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Hsecondary · psirt@fortinet.comexploitability 0.8 · impact 5.9

v3.16.1mediumCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-120USCWE-120USCWE-121USCWE-787US

affected products (145)

Products and version ranges known to be affected.

Fortinet FortiADC≤ 6.0.0 ≤6.0.4enisa_euvdEU
Fortinet FortiADC≤ 6.2.0 ≤6.2.2enisa_euvdEU
Fortinet FortiADC≤ 5.0.0 ≤5.0.4enisa_euvdEU
Fortinet FortiADC≤ 6.1.0 ≤6.1.5enisa_euvdEU
Fortinet FortiADC≤ 5.1.0 ≤5.1.7enisa_euvdEU
Fortinet FortiADC≤ 5.2.0 ≤5.2.8enisa_euvdEU
Fortinet FortiADC≤ 5.4.0 ≤5.4.5enisa_euvdEU
Fortinet FortiADC≤ 5.3.0 ≤5.3.7enisa_euvdEU
Fortinet FortiAnalyzer≤ 6.2.0 ≤6.2.13enisa_euvdEU
Fortinet FortiAnalyzer≤ 7.0.0 ≤7.0.2enisa_euvdEU
Fortinet FortiAnalyzer≤ 6.4.0 ≤6.4.7enisa_euvdEU
Fortinet FortiAnalyzer≤ 6.0.0 ≤6.0.12enisa_euvdEU
Fortinet FortiDDoS≤ 4.5.0enisa_euvdEU
Fortinet FortiDDoS≤ 4.4.0 ≤4.4.2enisa_euvdEU
Fortinet FortiDDoS≤ 4.7.0enisa_euvdEU
Fortinet FortiDDoS≤ 5.0.0enisa_euvdEU
Fortinet FortiDDoS≤ 5.5.0 ≤5.5.1enisa_euvdEU
Fortinet FortiDDoS≤ 4.6.0enisa_euvdEU
Fortinet FortiDDoS≤ 5.3.0 ≤5.3.2enisa_euvdEU
Fortinet FortiDDoS≤ 5.4.0 ≤5.4.3enisa_euvdEU

showing 20 of 145

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu NVD CVE.org MITRE

published 2021-12-08modified 2026-06-17

references (6)

External citations — patches, advisories, analysis.

scry

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