CVE-2021-43838 - CVE House
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Status published Medium CVE-2021-43838

Regular Expression Denial of Service (ReDoS) in jsx-slack

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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CVE-2021-43843
Insufficient patch for Regular Expression Denial of Service (ReDoS) to jsx-slack v4.5.1
Medium 5.3

Affected Vendor

Affected Software

jsx-slack
Vulnerable Versions:
< 4.5.1

Timeline

Official Publish: December 17th, 2021
Last Modified: August 4th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Weaknesses (CWE)

CWE-400

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1498 Network Denial of Service
Impact