CVE-2004-2137

CVE-2004-2137 is a medium-severity vulnerability in Microsoft Outlook Express with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 26% places it in the 98th percentile, indicating an elevated likelihood of exploitation.

Key facts

Description

Outlook Express 6.0, when sending multipart e-mail messages using the "Break apart messages larger than" setting, leaks the BCC recipients of the message to the addresses listed in the To and CC fields, which may allow remote attackers to obtain sensitive information.

Frequently asked questions

What is CVE-2004-2137?
Outlook Express 6.0, when sending multipart e-mail messages using the "Break apart messages larger than" setting, leaks the BCC recipients of the message to the addresses listed in the To and CC fields, which may allow remote attackers to obtain sensitive information.
How severe is CVE-2004-2137?
CVE-2004-2137 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2004-2137 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 26% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2004-2137?
CVE-2004-2137 primarily affects Microsoft Outlook Express. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2004-2137?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2004-2137 published?
CVE-2004-2137 was published on 2004-12-31 and last updated on 2026-06-16.

References

Affected products (2)

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