Is CVE-2004-1638 being exploited in the wild?

It is not listed in any known-exploited vulnerabilities catalog.

Is CVE-2004-1638 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2004-1638?

Public exploit code is available.

Is there a fix for CVE-2004-1638?

No fixed version is listed yet; check the vendor advisory for mitigations.

How urgently should CVE-2004-1638 be patched?

Brandefense priority: patch immediately, because it is very likely to be exploited soon.

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Vulnerability Intelligence

CVE-2004-1638

HighPublic exploit

Buffer overflow in MailCarrier 2.51 allows remote attackers to execute arbitrary code via a long (1) EHLO and possibly (2) HELO command.

Published Oct 16, 2004 · Updated Apr 15, 2026

Key Facts

Patch immediately

CVE-2004-1638 is a high-severity vulnerability (CVSS 7.5 v2).
It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
EPSS estimates a 63% probability of exploitation in the next 30 days.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

CVSS v2

7.5

AV:N/AC:L/Au:N/C:P/I:P/A:P

EPSS (30-day exploit likelihood)

63%

Higher than 99.1% of all scored CVEs

Exploited in the wild

No known

Not in a known-exploited catalog

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2004-1638 brief as a PDF

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Description

Buffer overflow in MailCarrier 2.51 allows remote attackers to execute arbitrary code via a long (1) EHLO and possibly (2) HELO command.

Timeline

Publicly disclosed
Oct 16, 2004
Last updated
Apr 15, 2026

References

3 more references in the full CVE brief

FAQ

Common Questions.

Buffer overflow in MailCarrier 2.51 allows remote attackers to execute arbitrary code via a long (1) EHLO and possibly (2) HELO command.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

Is CVE-2004-1638 Running On Your Attack Surface?

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