How severe is CVE-2020-6646?

CVE-2020-6646 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 user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-6646 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-6646?

CVE-2020-6646 primarily affects Fortinet Fortiweb. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-6646?

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

When was CVE-2020-6646 published?

CVE-2020-6646 was published on 2020-03-17 and last updated on 2026-06-17.

CVE-2020-6646

CVE-2020-6646 is a medium-severity vulnerability in Fortinet Fortiweb 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Fortinet Fortiweb
Published: 2020-03-17
Last modified: 2026-06-17

Description

An improper neutralization of input vulnerability in FortiWeb allows a remote authenticated attacker to perform a stored cross site scripting attack (XSS) via the Disclaimer Description of a Replacement Message.

Frequently asked questions

What is CVE-2020-6646?: An improper neutralization of input vulnerability in FortiWeb allows a remote authenticated attacker to perform a stored cross site scripting attack (XSS) via the Disclaimer Description of a Replacement Message.
How severe is CVE-2020-6646?: CVE-2020-6646 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 user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-6646 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-6646?: CVE-2020-6646 primarily affects Fortinet Fortiweb. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-6646?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-6646 published?: CVE-2020-6646 was published on 2020-03-17 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-20-001

Affected products (2)

cpe:2.3:a:fortinet:fortiweb:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiweb:6.3.0:*:*:*:*:*:*:*

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