How severe is CVE-2020-12819?

CVE-2020-12819 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2020-12819 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12819?

CVE-2020-12819 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-12819?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2020-12819 have an EU (EUVD) identifier?

Yes. CVE-2020-12819 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-5102.

When was CVE-2020-12819 published?

CVE-2020-12819 was published on 2024-12-19 and last updated on 2026-06-17.

CVE-2020-12819

CVE-2020-12819 is a medium-severity vulnerability in Fortinet Fortios with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2020-5102
Weakness: CWE-787
Affected product: Fortinet Fortios
Published: 2024-12-19
Last modified: 2026-06-17

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

Frequently asked questions

What is CVE-2020-12819?: 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
How severe is CVE-2020-12819?: CVE-2020-12819 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2020-12819 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12819?: CVE-2020-12819 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-12819?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2020-12819 have an EU (EUVD) identifier?: Yes. CVE-2020-12819 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-5102.
When was CVE-2020-12819 published?: CVE-2020-12819 was published on 2024-12-19 and last updated on 2026-06-17.

References

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

Affected products (1)

cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*

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