CVE-2022-45414 — If a Thunderbird user quoted from an HTML email, for example by replying to the

If a Thunderbird user quoted from an HTML email, for example by replying to the email, and the email contained either a VIDEO tag with the POSTER attribute or an OBJECT tag with a DATA attribute, a network request to the referenced remote URL was performed, regardless of a config

01What is this vulnerability?

If a Thunderbird user quoted from an HTML email, for example by replying to the email, and the email contained either a VIDEO tag with the POSTER attribute or an OBJECT tag with a DATA attribute, a network request to the referenced remote URL was performed, regardless of a configuration to block remote content. An image loaded from the POSTER attribute was shown in the composer window. These…

02Affected products

Vendor	Product	Versions
Mozilla	Thunderbird	unspecified

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2022-12-22T00:00:00.000Z
• Last modified: 2025-04-15T14:56:05.405Z

09References

• www.mozilla.org — https://www.mozilla.org/security/advisories/mfsa2022-50/
• bugzilla.mozilla.org — https://bugzilla.mozilla.org/show_bug.cgi?id=1788096