CVE-2004-2226

CVE-2004-2226 is a medium-severity vulnerability in Mozilla Thunderbird with a CVSS 2.0 base score of 5.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

Mozilla Mail 1.7.1 and 1.7.3, and Thunderbird before 0.9, when HTML-Mails is enabled, allows remote attackers to determine valid e-mail addresses via an HTML e-mail that references a Cascading Style Sheets (CSS) document on the attacker's server.

Frequently asked questions

What is CVE-2004-2226?
Mozilla Mail 1.7.1 and 1.7.3, and Thunderbird before 0.9, when HTML-Mails is enabled, allows remote attackers to determine valid e-mail addresses via an HTML e-mail that references a Cascading Style Sheets (CSS) document on the attacker's server.
How severe is CVE-2004-2226?
CVE-2004-2226 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2004-2226 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2004-2226?
CVE-2004-2226 primarily affects Mozilla Thunderbird. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2004-2226?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2004-2226 published?
CVE-2004-2226 was published on 2004-12-31 and last updated on 2026-06-16.

References

Affected products (3)

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