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CVE-2021-43838 Details

Description

jsx-slack is a library for building JSON objects for Slack Block Kit surfaces from JSX. In versions prior to 4.5.1 users are vulnerable to a regular expression denial-of-service (ReDoS) attack. If attacker can put a lot of JSX elements into `<blockquote>` tag, an internal regular expression for escaping characters may consume an excessive amount of computing resources. jsx-slack v4.5.1 has patched to a regex for escaping blockquote characters. Users are advised to upgrade as soon as possible.

Metrics

CVSS 3.x Severity and Vector Strings:

NIST: [email protected]CVSS-B:7.5 HIGHVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CNA: [email protected]CVSS-B:5.3 MEDIUMVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References to Advisories, Solutions, and Tools

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URL	Source(s)	Tag(s)
https://github.com/yhatt/jsx-slack/commit/36e4a10405e4c7745333e245fcc5029c02c7065d	CVE	PatchThird Party Advisory
https://github.com/yhatt/jsx-slack/security/advisories/GHSA-55xv-f85c-248q	CVE	ExploitPatchThird Party Advisory
https://github.com/yhatt/jsx-slack/commit/36e4a10405e4c7745333e245fcc5029c02c7065d	[email protected]	PatchThird Party Advisory
https://github.com/yhatt/jsx-slack/security/advisories/GHSA-55xv-f85c-248q	[email protected]	ExploitPatchThird Party Advisory

Weakness Enumeration

CWE-ID	CWE Name	Source
CWE-1333	Inefficient Regular Expression Complexity	[email protected]
CWE-400	Uncontrolled Resource Consumption	[email protected]

Affected Products

Product	Versions
jsx-slack project jsx-slack	< 4.5.2
CPE cpe:2.3:a:jsx-slack_project:jsx-slack::::::node.js::* Remediation No remediation found in references.

Change History

5 change records found show changes

Date	Action	Recorded By
Jun 17, 2026	CVE Modified	[email protected]
Nov 21, 2024	CVE Modified	CVE
May 14, 2024	CVE Modified	[email protected]
Jul 21, 2023	Reanalysis	[email protected]
Jan 3, 2022	Initial Analysis	[email protected]