CVE-2021-43838

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

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.

Categories

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.32%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: yhatt jsx-slack
Published at:
Updated at:

References

Link Tags
https://github.com/yhatt/jsx-slack/security/advisories/GHSA-55xv-f85c-248q patch third party advisory exploit
https://github.com/yhatt/jsx-slack/commit/36e4a10405e4c7745333e245fcc5029c02c7065d third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-43838?
CVE-2021-43838 has been scored as a medium severity vulnerability.
How to fix CVE-2021-43838?
To fix CVE-2021-43838, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43838 being actively exploited in the wild?
It is possible that CVE-2021-43838 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43838?
CVE-2021-43838 affects yhatt jsx-slack.
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