How severe is CVE-2004-0400?

CVE-2004-0400 has a CVSS 2.0 base score of 7.5, rated high severity.

Is CVE-2004-0400 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2004-0400?

CVE-2004-0400 affects University Of Cambridge Exim. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2004-0400?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2004-0400 published?

CVE-2004-0400 was published on 2004-07-07 and last updated on 2026-06-16.

CVE-2004-0400

CVE-2004-0400 is a high-severity vulnerability in University Of Cambridge Exim with a CVSS 2.0 base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 2.0 base score 7.5)
EPSS exploit prediction: 7% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: University Of Cambridge Exim
Published: 2004-07-07
Last modified: 2026-06-16

Description

Stack-based buffer overflow in Exim 4 before 4.33, when the headers_check_syntax option is enabled, allows remote attackers to cause a denial of service and possibly execute arbitrary code during the header check.

Frequently asked questions

What is CVE-2004-0400?: Stack-based buffer overflow in Exim 4 before 4.33, when the headers_check_syntax option is enabled, allows remote attackers to cause a denial of service and possibly execute arbitrary code during the header check.
How severe is CVE-2004-0400?: CVE-2004-0400 has a CVSS 2.0 base score of 7.5, rated high severity.
Is CVE-2004-0400 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2004-0400?: CVE-2004-0400 affects University Of Cambridge Exim. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2004-0400?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2004-0400 published?: CVE-2004-0400 was published on 2004-07-07 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:university_of_cambridge:exim:*:*:*:*:*:*:*:*

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