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CVE-2003-0838Internet Explorer Vulnerability

Internet Explorer allows remote attackers to bypass zone restrictions to inject and execute arbitrary programs by creating a popup window and inserting ActiveX object code with a "data" tag pointing to the malicious code, which Internet Explorer treats as HTML or Javascript, but…

Published Nov 17, 2003 · Updated Apr 15, 2026

Key Facts

Patch immediately
  • CVE-2003-0838 is a high-severity vulnerability (CVSS 7.5 v2) affecting Ie (Microsoft), Internet Explorer (Microsoft).
  • It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
  • EPSS estimates a 38% 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 public exploit code exists for a high-severity flaw.

Scores

CVSS v2

7.5

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

EPSS (30-day exploit likelihood)

38%

Higher than 98.5% of all scored CVEs

Exploit maturity

Proof of concept

ATLAS score

35/100

Publication score, see How it works

Exploitation Verdict

KEV listed

Not listed

Federal due date

None

No federal due date

Ransomware use

Not reported

Attributed actors

None named

Exploit & Defence Guidance

Exploit maturity

Proof of concept

Public exploit code

1

Proof-of-concept links

In-the-wild evidence

0

Reports of active use

Description

Internet Explorer allows remote attackers to bypass zone restrictions to inject and execute arbitrary programs by creating a popup window and inserting ActiveX object code with a "data" tag pointing to the malicious code, which Internet Explorer treats as HTML or Javascript, but later executes as an HTA application, a different vulnerability than CVE-2003-0532, and as exploited using the QHosts Trojan horse (aka Trojan.Qhosts, QHosts-1, VBS.QHOSTS, or aolfix.exe).

Affected Products

9 affected entries in total
ProductAffected versionsFixed in
IeMicrosoft6.0-sp1n/a
Internet ExplorerMicrosoft5.0.1, 5.0.1-sp1, 5.0.1-sp2, 5.0.1-sp3, 5.5, 5.5-sp1, 5.5-sp2, 6.0n/a

Timeline

  1. Publicly disclosed

    Nov 17, 2003

  2. Last updated

    Apr 15, 2026

FAQ

Common Questions.

Is CVE-2003-0838 On Your Attack Surface?

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Figures as of Oct 20, 2026. Compiled by Brandefense technologies from public vulnerability catalogs; scoring as described in How it works.

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