CVE-2021-26109

highpriority · track · 40EPSS 0.019 · 79 %ileEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.88% (79th) EPSS

CVSS 7.5 · high

Is it mine?

9 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-22

An integer overflow or wraparound vulnerability in the memory allocator of SSLVPN in FortiOS before 7.0.1 may allow an unauthenticated attacker to corrupt control data on the heap via specifically crafted requests to SSLVPN, resulting in potentially arbitrary code execution.

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

v3.18.1highAV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:U/RC:Csecondary · ENISA EU

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · psirt@fortinet.comexploitability 2.2 · 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-190USprimaryCWE-190US

affected products (9)

Products and version ranges known to be affected.

Fortinet Fortinet FortiOS≤ FortiOS before 7.0.1enisa_euvdEU
Fortinet Inc. FortiOS≤ 7.0.0fstec_bduRU
Fortinet Inc. FortiOS≤ 6.0.12fstec_bduRU
Fortinet Inc. FortiOS6.2.0 → 6.2.9fstec_bduRU
Fortinet Inc. FortiOS6.4.0 → 6.4.5fstec_bduRU
fortinet fortios6.0.0 → 6.0.12nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios6.2.0 → 6.2.9nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios6.4.0 → 6.4.5nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios= 7.0.0nvdUScpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*

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 2021-12-08modified 2026-06-17

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+4620 more

references (8)

External citations — patches, advisories, analysis.

scry

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