How severe is CVE-2020-15936?

CVE-2020-15936 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over an adjacent network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-15936 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-15936?

CVE-2020-15936 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-15936?

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

When was CVE-2020-15936 published?

CVE-2020-15936 was published on 2022-03-01 and last updated on 2026-06-17.

CVE-2020-15936

CVE-2020-15936 is a low-severity vulnerability in Fortinet Fortios with a CVSS 3.x base score of 2.6. 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-20.

Key facts

Severity: Low (CVSS 3.x base score 2.6)
CVSS v2: 4.0
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Fortinet Fortios
Published: 2022-03-01
Last modified: 2026-06-17

Description

A improper input validation in Fortinet FortiGate version 6.4.3 and below, version 6.2.5 and below, version 6.0.11 and below, version 5.6.13 and below allows attacker to disclose sensitive information via SNI Client Hello TLS packets.

Frequently asked questions

What is CVE-2020-15936?: A improper input validation in Fortinet FortiGate version 6.4.3 and below, version 6.2.5 and below, version 6.0.11 and below, version 5.6.13 and below allows attacker to disclose sensitive information via SNI Client Hello TLS packets.
How severe is CVE-2020-15936?: CVE-2020-15936 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over an adjacent network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-15936 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-15936?: CVE-2020-15936 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-15936?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-15936 published?: CVE-2020-15936 was published on 2022-03-01 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-20-091

Affected products (1)

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

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