Is CVE-2004-0840 being actively exploited?

CVE-2004-0840 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2004-0840?

CVE-2004-0840 has a CVSS 2.0 base score of 10.0 (HIGH).

CVE-2004-0840

HIGH · CVSS 10.0EPSS 30.3%EU EUVD

The SMTP (Simple Mail Transfer Protocol) component of Microsoft Windows XP 64-bit Edition, Windows Server 2003, Windows Server 2003 64-bit Edition, and the Exchange Routing Engine component of Exchange Server 2003, allows remote attackers to execute arbitrary code via a malicious DNS response message containing length values that are not properly validated.

Key facts

CVSS score: 10.0 (v2.0)
Severity: HIGH
CVSS vector: AV:N/AC:L/Au:N/C:C/I:C/A:C
Weakness (CWE): CWE-20
EPSS score: 30.3% (98th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2004-0838)
Published: November 3, 2004
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2004-0838 in the EU Vulnerability Database. Last updated in EUVD on August 8, 2024.

View on the EU Vulnerability Database

Affected products

microsoft / exchange server
microsoft / windows server 2003
microsoft / windows server 2003
microsoft / windows xp

Certified products that may be affected

4 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Windows XP Enhanced Cryptographic Provider (RSAENH) - Microsoft Corporation - FIPS 140 989 - historical
Windows XP Enhanced DSS and Diffie-Hellman Cryptographic Provider (DSSENH) - Microsoft Corporation - FIPS 140 990 - historical
Microsoft Windows Server 2003 SP2 including R2, Standard, Enterprise, Datacenter, x64, and Itanium Editions; Windows XP Professional SP2 and x64 SP2; Windows XP Embedded SP2 - Microsoft Corporation - Common Criteria CCEVS-VR-VID-10184-2008 - archived
Microsoft Windows 2003 and Microsoft Windows XP - Microsoft Corporation - Common Criteria CCEVS-VR-0131-2005 - archived

References

http://www.kb.cert.org/vuls/id/394792(Patch, Third Party Advisory, US Government Resource)
http://www.securityfocus.com/bid/11374(Third Party Advisory, VDB Entry)
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2004/ms04-035(Patch, Vendor Advisory)
https://exchange.xforce.ibmcloud.com/vulnerabilities/17621(Third Party Advisory, VDB Entry)
https://exchange.xforce.ibmcloud.com/vulnerabilities/17660(Third Party Advisory, VDB Entry)
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A2300(Third Party Advisory)
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A3460(Third Party Advisory)
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5509(Third Party Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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