CVE-2021-43838 : Security Advisory and Response

A vulnerability in jsx-slack library versions prior to 4.5.1 could lead to a Regular Expression Denial of Service (ReDoS) attack due to uncontrolled resource consumption.

Understanding CVE-2021-43838

What is CVE-2021-43838?

jsx-slack, a library for generating Slack Block Kit JSON objects from JSX, is susceptible to a ReDoS attack when < 4.5.1, potentially allowing attackers to exhaust computational resources.

The Impact of CVE-2021-43838

The vulnerability can result in a ReDoS attack, impacting the availability of services using jsx-slack, with a CVSS base score of 5.3 (Medium severity).

Technical Details of CVE-2021-43838

Vulnerability Description

Users of versions prior to 4.5.1 are vulnerable to a ReDoS attack if malicious JSX elements are placed within a

<blockquote>

tag due to uncontrolled resource consumption.

Affected Systems and Versions

Product: jsx-slack
Vendor: yhatt
Versions Affected: < 4.5.1

Exploitation Mechanism

An attacker can exploit the vulnerability by inserting a significant number of JSX elements into a

<blockquote>

tag, causing excessive resource consumption.

Mitigation and Prevention

Immediate Steps to Take

Upgrade to version 4.5.1 of jsx-slack to mitigate the vulnerability.

Long-Term Security Practices

Regularly update software libraries to patch known vulnerabilities.

Patching and Updates

Update jsx-slack to the latest version to ensure security against ReDoS attacks.