TI-2020-10188 Aliases CVE-2020-12819 GHSA-8vr7-33jp-gfgw

Heap-based buffer overflow in Fortinet FortiOS

LOW 34CWE-122Published 2024-12-19 · Updated 2024-12-20

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: High
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-122 and the CVSS impact.

Summary

A heap-based buffer overflow vulnerability in the processing of Link Control Protocol messages in FortiGate versions 5.6.12, 6.0.10, 6.2.4 and 6.4.1 and earlier may allow a remote attacker with valid SSL VPN credentials to crash the SSL VPN daemon by sending a large LCP packet, when tunnel mode is enabled. Arbitrary code execution may be theoretically possible, albeit practically very difficult to achieve in this context

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00792 56th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Fortinet	FortiOS	6.4.0 – 6.4.1; 6.2.0 – 6.2.4; 6.0.0 – 6.0.10; 5.6.0 – 5.6.12	—	No fix listed	CNA

FortiOS VendorFortinet Affected 6.4.0 – 6.4.1; 6.2.0 – 6.2.4; 6.0.0 – 6.0.10; 5.6.0 – 5.6.12 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:o:fortinet:fortios::::::::	before 5.6.13; 6.0.0 to before 6.0.11; 6.2.0 to before 6.2.5; 6.4.0 to before 6.4.2	Vulnerable	Fortinet

cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:* Versions before 5.6.13; 6.0.0 to before 6.0.11; 6.2.0 to before 6.2.5; 6.4.0 to before 6.4.2 Vulnerable ·Fortinet

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2020-12819
2026-10-03 Alias added: GHSA-8vr7-33jp-gfgw

References

Advisory 1

https://fortiguard.com/advisory/FG-IR-20-082

TI-2026-20057 Authentication bypass in Fortinet FortiWeb KEVCVSS 3.1CRITICAL 9.4
TI-2025-18911 Heap-based buffer overflow in Fortinet FortiSwitchManager KEVCVSS 3.1CRITICAL 9.8
TI-2024-36904 Authentication bypass in Fortinet FortiOS KEVCVSS 3.1CRITICAL 9.8
TI-2024-15234 A use of externally-controlled format string in Fortinet FortiOS versions 7.4.0 through… KEVCVSS 3.1CRITICAL 9.8
TI-2024-14448 Out-of-bounds write in Fortinet FortiOS KEVCVSS 3.1CRITICAL 9.8
TI-2023-12585 Heap-based buffer overflow in Fortinet FortiOS-6K7K KEVCVSS 3.1CRITICAL 9.8

See all 276 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences