CVE-2021-43843
5.3 · MEDIUMOverview
CVE-2021-43843 is a medium-severity vulnerability affecting jsx-slack_project jsx-slack. It was published on December 20, 2021 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
jsx-slack is a package for building JSON objects for Slack block kit surfaces from JSX. The maintainers found the patch for CVE-2021-43838 in jsx-slack v4.5.1 is insufficient tfor protection from a Regular Expression Denial of Service (ReDoS) attack. If an attacker can put a lot of JSX elements into `<blockquote>` tag _with including multibyte characters_, an internal regular expression for escaping characters may consume an excessive amount of computing resources. v4.5.1 passes the test against ASCII characters but misses the case of multibyte characters. jsx-slack v4.5.2 has updated regular expressions for escaping blockquote characters to prevent catastrophic backtracking. It is also including an updated test case to confirm rendering multiple tags in `<blockquote>` with multibyte characters.
Remediation
Check the references section for vendor advisories and patches from jsx-slack_project. Update jsx-slack to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| jsx-slack_project | jsx-slack | >= 0, < 4.5.2 | Affected |
References
Frequently Asked Questions
What is CVE-2021-43843?
CVE-2021-43843 is a medium-severity vulnerability affecting jsx-slack_project jsx-slack. It was published on December 20, 2021 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2021-43843?
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-43843?
Check the references section for vendor advisories and patches from jsx-slack_project. Update jsx-slack to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-43843?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-43843 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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