Cyber Resilience

CVE-2020-12820

Medium

Published: 19 December 2024

Published
19 December 2024
Modified
21 January 2025
KEV Added
Patch
CVSS Score v3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
EPSS Score 0.0404 88.8th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2020-12820 is a medium-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Fortinet Fortios. Its CVSS base score is 5.4 (Medium).

Operationally, ranked in the top 11.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

requesting a large FortiClient file name. We are not aware of proof of concept code successfully achieving the latter.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

fortinet
fortios
≤ 5.6.13 · 6.0.0 — 6.0.11

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

References