CVE-2021-43838

MEDIUM

jsx-slack <4.5.1 - DoS

Title source: llm
STIX 2.1

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.

References (2)

Core 2
Core References
Exploit, Patch, Third Party Advisory x_refsource_confirm
https://github.com/yhatt/jsx-slack/security/advisories/GHSA-55xv-f85c-248q

Scores

CVSS v3 5.3
EPSS 0.0033
EPSS Percentile 56.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Details

CWE
CWE-1333 CWE-400
Status published
Products (2)
jsx-slack_project/jsx-slack < 4.5.2
npm/jsx-slack 0 - 4.5.1npm
Published Dec 17, 2021
Tracked Since Feb 18, 2026