How severe is CVE-2009-3943?

CVE-2009-3943 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2009-3943 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-3943?

CVE-2009-3943 affects Microsoft Internet Explorer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-3943?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2009-3943 published?

CVE-2009-3943 was published on 2009-11-16 and last updated on 2026-06-16.

CVE-2009-3943

CVE-2009-3943 is a medium-severity vulnerability in Microsoft Internet Explorer with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 13% places it in the 96th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 13% (96th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Internet Explorer
Published: 2009-11-16
Last modified: 2026-06-16

Description

Microsoft Internet Explorer 6 through 6.0.2900.2180 and 7 through 7.0.6000.16711 allows remote attackers to cause a denial of service (application hang) via a JavaScript loop that configures the home page by using the setHomePage method and a DHTML behavior property.

Frequently asked questions

What is CVE-2009-3943?: Microsoft Internet Explorer 6 through 6.0.2900.2180 and 7 through 7.0.6000.16711 allows remote attackers to cause a denial of service (application hang) via a JavaScript loop that configures the home page by using the setHomePage method and a DHTML behavior property.
How severe is CVE-2009-3943?: CVE-2009-3943 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2009-3943 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-3943?: CVE-2009-3943 affects Microsoft Internet Explorer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-3943?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-3943 published?: CVE-2009-3943 was published on 2009-11-16 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:microsoft:internet_explorer:*:*:*:*:*:*:*:*

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