CVE-2007-3896

CVE-2007-3896 is a critical-severity vulnerability in Microsoft Internet Explorer with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 54% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Description

The URL handling in Shell32.dll in the Windows shell in Microsoft Windows XP and Server 2003, with Internet Explorer 7 installed, allows remote attackers to execute arbitrary programs via invalid "%" sequences in a mailto: or other URI handler, as demonstrated using mIRC, Outlook, Firefox, Adobe Reader, Skype, and other applications. NOTE: this issue might be related to other issues involving URL handlers in Windows systems, such as CVE-2007-3845. There also might be separate but closely related issues in the applications that are invoked by the handlers.

Frequently asked questions

What is CVE-2007-3896?
The URL handling in Shell32.dll in the Windows shell in Microsoft Windows XP and Server 2003, with Internet Explorer 7 installed, allows remote attackers to execute arbitrary programs via invalid "%" sequences in a mailto: or other URI handler, as demonstrated using mIRC, Outlook, Firefox, Adobe Reader, Skype, and other applications. NOTE: this issue might be related to other issues involving URL handlers in Windows systems, such as CVE-2007-3845. There also might be separate but closely related issues in the applications that are invoked by the handlers.
How severe is CVE-2007-3896?
CVE-2007-3896 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2007-3896 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 54% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2007-3896?
CVE-2007-3896 affects Microsoft Internet Explorer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2007-3896?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2007-3896 published?
CVE-2007-3896 was published on 2007-10-11 and last updated on 2026-06-16.

References

Affected products (1)

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