VULNERABILITY INTELLIGENCE
CVE-2021-43838
CVSS score5.3 MEDIUM
EPSS probability1.42%
CISA KEVNot currently listed
Published2021-12-17
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
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.
Weakness classification
- security-advisories@github.com: CWE-400
- nvd@nist.gov: CWE-1333
Primary references
- security-advisories@github.com — Patch, Third Party Advisory
- security-advisories@github.com — Exploit, Patch, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Exploit, Patch, Third Party Advisory