CVE-2020-12819

HIGH

7.5

CVSS Score

Published: December 19, 2024 at 07:40 AM UTC

Updated: June 17, 2026 at 02:52 AM UTC

1 product affected across 1 vendorFortiOS

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Severity

HIGH7.5

Exploit prediction

EPSS 0.8%

SSVC

No known exploit

Description

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

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

FortiOS · Fortinet

95%

v < 5.6.135.6.0 ≤ v ≤ 5.6.126.0.0 ≤ v ≤ 6.0.106.0.0 ≤ v < 6.0.116.2.0 ≤ v ≤ 6.2.46.2.0 ≤ v < 6.2.56.4.0 ≤ v ≤ 6.4.16.4.0 ≤ v < 6.4.25.6.0 5.6.1 5.6.10 5.6.11 5.6.12 5.6.2 5.6.3 5.6.4 5.6.5 5.6.6 5.6.7 5.6.8 5.6.9 6.0.0 6.0.1 6.0.10 6.0.2 6.0.3 6.0.4 6.0.5 6.0.6 6.0.7 6.0.8 6.0.9 6.2.0 6.2.1 6.2.2 6.2.3 6.2.4 6.4.0 6.4.1

Affected range stops below 5.6.13, so it looks safe — our inference, not a vendor statement

Affected range stops below 6.0.11, so it looks safe — our inference, not a vendor statement

Affected range stops below 6.2.5, so it looks safe — our inference, not a vendor statement

Affected range stops below 6.4.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

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

References (1)

Vendor Advisory

Source: [email protected]

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

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGH[email protected]

Attack Vector: NETWORK
Complexity: HIGH
Privileges: LOW
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: HIGH
Integrity: HIGH
Availability: HIGH

Vector?

Quick Info

StatusANALYZED

CWE

CWE-122CWE-787

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