CVE-2005-4840

What it is

The Outlook Express Address Book control, when using Internet Explorer 6, allows remote attackers to cause a denial of service (NULL dereference and browser crash) by creating the OutlookExpress.AddressBook COM object, which is not intended for use within Internet Explorer.

At a glance

Exploitability

Can be exploited over the network without logging in. Limited direct impact.

Exploit odds

11.5% chance of exploitation in the next 30 days (EPSS). Higher than most.

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2005-12-31 05:00 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-16 22:19 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 11.5% in the next 30 days (EPSS).
• Severity: 4.3 MEDIUM (CVSS).
• Fix: none linked yet, which raises it.

Details

Published

2005-12-31 05:00 UTC

Last modified

2026-06-16 22:19 UTC

Exploit probability

11.5% · EPSS, next 30 days

Weakness

CWE-119 · Buffer errors

Record status

Modified

Affected

• Microsoft Outlook Express Book Control

Attack profile CVSS 2.0 · 4.3

Attack vector

Network

Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

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-2005-4840.md and follow it. Check whether this project is affected by CVE-2005-4840. 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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