CVE-2021-36167
mediumpriority · track · 21EPSS 0.006 · 49 %ileEUUSEPSS · scored 2026-10-27
An improper authorization vulnerabiltiy [CWE-285] in FortiClient Windows versions 7.0.0 and 6.4.6 and below and 6.2.8 and below may allow an unauthenticated attacker to bypass the webfilter control via modifying the session-id paramater.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
- Fortinet Fortinet FortiClientWindows≤ FortiClientWindows 7.0.0, 6.4.6, 6.4.5, 6.4.4, 6.4.3, 6.4.2, 6.4.1, 6.4.0, 6.2.8, 6.2.7, 6.2.6, 6.2.5, 6.2.4, 6.2.3, 6.2.2, 6.2.1, 6.2.0enisa_euvdEU
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (5)
External citations — patches, advisories, analysis.
- https://fortiguard.com/advisory/FG-IR-20-127cnnvd
- https://vigilance.fr/vulnerability/FortiClient-Windows-ingress-filtrering-bypass-via-Session-id-Web-Filter-Bypass-37018cnnvd
- https://www.mozilla.org/security/advisories/mfsa2021-52/Patchcnnvd
- https://fortiguard.com/advisory/FG-IR-20-127enisa_euvd
- https://fortiguard.com/advisory/FG-IR-20-127PatchVendor Advisorynvd
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