CVE-2021-43808

Name: CVE-2021-43808
Creator: NVD / NIST
Published: 2021-12-08T00:15:07.683+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 0.80%

Last modified Jun 17, 2026

CVE-2021-43808 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. 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. EPSS estimates a 0.80% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

6.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

0.80%

51.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Laravel	Framework	< 6.20.42
Laravel	Framework	>= 7.0.0, < 7.30.6
Laravel	Framework	>= 8.0.0, < 8.75.0

References

https://github.com/laravel/framework/commit/b8174169b1807f36de1837751599e2828ceddb9bPatch, Third Party Advisory
https://github.com/laravel/framework/pull/39906Patch, Third Party Advisory
https://github.com/laravel/framework/pull/39908Patch, Third Party Advisory
https://github.com/laravel/framework/pull/39909Patch, Third Party Advisory
https://github.com/laravel/framework/releases/tag/v6.20.42Release Notes, Third Party Advisory
https://github.com/laravel/framework/releases/tag/v7.30.6Release Notes, Third Party Advisory
https://github.com/laravel/framework/releases/tag/v8.75.0Release Notes, Third Party Advisory
https://github.com/laravel/framework/security/advisories/GHSA-66hf-2p6w-jqfwExploit, Third Party Advisory
https://github.com/laravel/framework/commit/b8174169b1807f36de1837751599e2828ceddb9bPatch, Third Party Advisory
https://github.com/laravel/framework/pull/39906Patch, Third Party Advisory
https://github.com/laravel/framework/pull/39908Patch, Third Party Advisory
https://github.com/laravel/framework/pull/39909Patch, Third Party Advisory
https://github.com/laravel/framework/releases/tag/v6.20.42Release Notes, Third Party Advisory
https://github.com/laravel/framework/releases/tag/v7.30.6Release Notes, Third Party Advisory
https://github.com/laravel/framework/releases/tag/v8.75.0Release Notes, Third Party Advisory
https://github.com/laravel/framework/security/advisories/GHSA-66hf-2p6w-jqfwExploit, Third Party Advisory

Timeline

Published: Dec 8, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-43808?

How severe is CVE-2021-43808?

CVE-2021-43808 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 0.80% probability of exploitation in the next 30 days.

How do I fix CVE-2021-43808?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-43808?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST