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CVE-2021-36173

HIGH severity · CVSS 8 · Out-of-bounds write
8CVSS HIGH

Summary

A heap-based buffer overflow in the firmware signature verification function of FortiOS versions 7.0.1, 7.0.0, 6.4.0 through 6.4.6, 6.2.0 through 6.2.9, and 6.0.0 through 6.0.13 may allow an attacker to execute arbitrary code via specially crafted installation images.

Impact & exploitability

Attack vectorAdjacent
Attack complexityLow
Privileges requiredNone
User interactionRequired
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
Exploit probability (EPSS)1%

CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products we track (1)

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Official patch: https://fortiguard.com/advisory/FG-IR-21-115 ↗