CVE-2020-12820
Last modified
CVE-2020-12820 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. Under non-default configuration, a stack-based buffer overflow in FortiOS version 6.0.10 and below, version 5.6.12 and below may allow a remote attacker authenticated to the SSL VPN to crash the FortiClient NAC daemon (fcnacd) and potentially execute arbitrary code via requesting a large FortiClient file name. We are not aware of proof of concept code successfully achieving the latter.. EPSS estimates a 0.86% chance of exploitation in the next 30 days.
Description
Under non-default configuration, a stack-based buffer overflow in FortiOS version 6.0.10 and below, version 5.6.12 and below may allow a remote attacker authenticated to the SSL VPN to crash the FortiClient NAC daemon (fcnacd) and potentially execute arbitrary code via requesting a large FortiClient file name. We are not aware of proof of concept code successfully achieving the latter.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Fortinet | Fortios | < 5.6.13 |
| Fortinet | Fortios | >= 6.0.0, < 6.0.11 |
References
- https://fortiguard.fortinet.com/psirt/FG-IR-20-083Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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