CVE-2021-32671

CRITICAL Year: 2021
CVSS v3 Score
10.0
Critical
CVSS v2 Score
4.3
Medium
Weakness Type
CWE-79
View all →

Vulnerability Description

Flarum is a forum software for building communities. Flarum's translation system allowed for string inputs to be converted into HTML DOM nodes when rendered. This change was made after v0.1.0-beta.16 (our last beta before v1.0.0) and was not noticed or documented. This allowed for any user to type malicious HTML markup within certain user input fields and have this execute on client browsers. The example which led to the discovery of this vulnerability was in the forum search box. Entering faux-malicious HTML markup, such as <script>alert('test')</script> resulted in an alert box appearing on the forum. This attack could also be modified to perform AJAX requests on behalf of a user, possibly deleting discussions, modifying their settings or profile, or even modifying settings on the Admin panel if the attack was targetted towards a privileged user. All Flarum communities that run flarum v1.0.0 or v1.0.1 are impacted. The vulnerability has been fixed and published as flarum/core v1.0.2. All communities running Flarum v1.0 have to upgrade as soon as possible to v1.0.2.

Related Vulnerabilities

CVE-2023-0776

CRITICAL
CVSS:10.0(Critical)

Baicells Nova 436Q, Nova 430E, Nova 430I, and Neutrino 430 LTE TDD eNodeB devices with firmware through QRTB 2.12.7 are vulnerable to remote shell code exploitation via HTTP command injections. Comman...

CWE-792023

CVE-2024-47875

CRITICAL
CVSS:10.0(Critical)

DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to nesting-based mXSS. This vulnerability is fixed in 2.5.0 and 3.1.3.

CWE-792024

CVE-2019-13478

CRITICAL
CVSS:9.9(Critical)

The Yoast SEO plugin before 11.6-RC5 for WordPress does not properly restrict unfiltered HTML in term descriptions.

CWE-792019

CVE-2020-7741

CRITICAL
CVSS:9.9(Critical)

This affects the package hellojs before 1.18.6. The code get the param oauth_redirect from url and pass it to location.assign without any check and sanitisation. So we can simply pass some XSS payload...

CWE-792020

CVE-2021-42940

CRITICAL
CVSS:9.9(Critical)

A Cross Site Scripting (XSS) vulnerability exists in Projeqtor 9.3.1 via /projeqtor/tool/saveAttachment.php, which allows an attacker to upload a SVG file containing malicious JavaScript code.

CWE-792021

CVE-2022-1571

CRITICAL
CVSS:9.9(Critical)

Cross-site scripting - Reflected in Create Subaccount in GitHub repository neorazorx/facturascripts prior to 2022.07. This vulnerability can be arbitrarily executed javascript code to steal user'cooki...

CWE-792022
resulted in an alert box appearing on the forum. This attack could also be modified to perform AJAX requests on behalf of a user, possibly deleting discussions, modifying their settings or profile, or even modifying settings on the Admin panel if the attack was targetted towards a privileged user. All Flarum communities that run flarum v1.0.0 or v1.0.1 are impacted. The vulnerability has been fixed and published as flarum/core v1.0.2. All communities running Flarum v1.0 have to upgrade as soon as possible to v1.0.2." } }, { "@type": "Question", "name": "How severe is CVE-2021-32671?", "acceptedAnswer": { "@type": "Answer", "text": "This vulnerability has a severity rating of CRITICAL with a CVSS score of 10 out of 10." } }, { "@type": "Question", "name": "What type of vulnerability is CVE-2021-32671?", "acceptedAnswer": { "@type": "Answer", "text": "This is classified as CWE-79, which is a common weakness in software security." } } ] }