CVE-2019-16151: [FortiOS][Web filtering] Host header is vulnerable to an XSS vulnerability and redirection/injection

Published Sep 7, 2021
·
Updated

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.

Other sources

An improper neutralization of input during web page generation vulnerability [CWE-79] in FortiOS 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.

FortiGuard

Affected Software

3 affected components
Fortinet FortiOS<6.4.1, <6.2.9
Fortinet FortiOS>=6.2.0<6.2.10
Fortinet FortiOS>=6.4.0<6.4.2

Remediation

Information

Please upgrade to FortiOS version 6.4.2 or above. Please upgrade to FortiOS version 6.2.10 or above.

Event History

Sep 7, 2021
Advisory Published
via FortiGuard·12:00 AM
Data Sourced
via FortiGuard·12:00 AM
DescriptionSeverityWeaknessAffected Software
Oct 25, 2024
Advisory Published
via FortiGuard·12:00 AM
Mar 21, 2025
CVE Published
via MITRE·04:02 PM
Data Sourced
via MITRE·04:02 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2019-16151?

CVE-2019-16151 is classified as a medium severity vulnerability due to its potential to allow exploitation by remote unauthenticated attackers.

2

What types of attacks can be executed via CVE-2019-16151?

CVE-2019-16151 can allow attackers to redirect users to malicious websites or execute arbitrary JavaScript code.

3

Which versions of FortiOS are affected by CVE-2019-16151?

CVE-2019-16151 affects FortiOS versions 6.4.1 and below, and 6.2.9 and below.

4

How do I fix CVE-2019-16151?

To mitigate CVE-2019-16151, upgrade FortiOS to the latest version that addresses this vulnerability.

5

Is user authentication needed to exploit CVE-2019-16151?

No, CVE-2019-16151 can be exploited by remote unauthenticated attackers.

Contact

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info@secalerts.co
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