CVE-2021-43808

Description

Laravel is a web application framework. Laravel prior to versions 8.75.0, 7.30.6, and 6.20.42 contain a possible cross-site scripting (XSS) vulnerability in the Blade templating engine. A broken HTML element may be clicked and the user taken to another location in their browser due to XSS. This is due to the user being able to guess the parent placeholder SHA-1 hash by trying common names of sections. If the parent template contains an exploitable HTML structure an XSS vulnerability can be exposed. This vulnerability has been patched in versions 8.75.0, 7.30.6, and 6.20.42 by determining the parent placeholder at runtime and using a random hash that is unique to each request.

How to fix CVE-2021-43808

To remediate CVE-2021-43808, upgrade the affected package to a fixed version below.

• —upgrade to 6.20.14+dfsg-2+deb11u1 or later
• —upgrade to 6.20.42 or later
• —upgrade to 6.20.42 or later

Is CVE-2021-43808 being exploited?

Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.

Affected packages (3)

• from 0, < 6.20.14+dfsg-2+deb11u1
• from 0, < 6.20.42
• from 0, < 6.20.42

CVSS scores

References (13)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2021-43808
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2021-43808
• PATCHgithub.com/laravel/framework
• WEBgithub.com/FriendsOfPHP/security-advisories/blob/master/illuminate/view/CVE-2021-43808.yaml