CVE-2005-0021

What it is

Multiple buffer overflows in Exim before 4.43 may allow attackers to execute arbitrary code via (1) an IPv6 address with more than 8 components, as demonstrated using the -be command line option, which triggers an overflow in the host_aton function, or (2) the -bh command line option or dnsdb PTR lookup, which triggers an overflow in the dns_build_reverse function.

At a glance

Exploitability

Can be exploited locally on the machine without logging in. High risk of data exposure, data tampering, service disruption.

Exploit odds

2.6% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2005-05-02 04:00 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-16 22:10 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 2.6% in the next 30 days (EPSS).
• Severity: 7.2 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2005-05-02 04:00 UTC

Last modified

2026-06-16 22:10 UTC

Exploit probability

2.6% · EPSS, next 30 days

Record status

Modified

Affected

• University Of Cambridge Exim ≤ 4.40
• University Of Cambridge Exim 4.41
• University Of Cambridge Exim 4.42

Attack profile CVSS 2.0 · 7.2

Attack vector

Local

Complexity

Low

Authentication

None

Confidentiality

Complete

Integrity

Complete

Availability

Complete

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2005-0021.md and follow it. Check whether this project is affected by CVE-2005-0021. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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