How severe is CVE-2019-16151?

CVE-2019-16151 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2019-16151 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-16151?

CVE-2019-16151 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-16151?

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

Does CVE-2019-16151 have an EU (EUVD) identifier?

Yes. CVE-2019-16151 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-7234.

When was CVE-2019-16151 published?

CVE-2019-16151 was published on 2025-03-21 and last updated on 2026-06-17.

CVE-2019-16151

CVE-2019-16151 is a medium-severity vulnerability in Fortinet Fortios with a CVSS 3.x base score of 4.7. 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 4.7)
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-7234
Weakness: CWE-79
Affected product: Fortinet Fortios
Published: 2025-03-21
Last modified: 2026-06-17

Description

An improper neutralization of input during web page generation vulnerability [CWE-79] in FortiOS 6.4.1 and below, 6.2.9 and below may allow a remote unauthenticated attacker to either redirect users to malicious websites via a crafted "Host" header or to execute JavaScript code in the victim's browser context. This happens when the FortiGate has web filtering and category override enabled/configured.

Frequently asked questions

What is CVE-2019-16151?: An improper neutralization of input during web page generation vulnerability [CWE-79] in FortiOS 6.4.1 and below, 6.2.9 and below may allow a remote unauthenticated attacker to either redirect users to malicious websites via a crafted "Host" header or to execute JavaScript code in the victim's browser context. This happens when the FortiGate has web filtering and category override enabled/configured.
How severe is CVE-2019-16151?: CVE-2019-16151 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2019-16151 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-16151?: CVE-2019-16151 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-16151?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2019-16151 have an EU (EUVD) identifier?: Yes. CVE-2019-16151 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-7234.
When was CVE-2019-16151 published?: CVE-2019-16151 was published on 2025-03-21 and last updated on 2026-06-17.

References

https://fortiguard.com/advisory/FG-IR-19-301

Affected products (1)

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

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