CVE-2021-24020

highpriority · track · 39EPSS 0.006 · 49 %ileEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.62% (49th) EPSS

CVSS 7.5 · high

Is it mine?

5 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-26

A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.

cvss

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

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.17.5highAV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · psirt@fortinet.comexploitability 1.6 · impact 5.9

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-347USprimaryCWE-325US

affected products (5)

Products and version ranges known to be affected.

Fortinet Fortinet FortiMail≤ FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7enisa_euvdEU
Fortinet Inc. FortiMail≤ 6.2.6fstec_bduRU
Fortinet Inc. FortiMail6.4.0 → 6.4.4fstec_bduRU
fortinet fortimail6.2.0 → 6.2.7nvdUScpe:2.3:a:fortinet:fortimail:*:*:*:*:*:*:*:*
fortinet fortimail6.4.0 → 6.4.5nvdUScpe:2.3:a:fortinet:fortimail:*:*:*:*:*:*:*:*

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 NVD CVE.org MITRE

published 2021-07-09modified 2026-06-17

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+1039 more

references (6)

External citations — patches, advisories, analysis.

scry

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