CVE-2007-3896
CriticalExploitedPublic exploitThe 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,…
Published Oct 10, 2007 · Updated Apr 22, 2026
Key Facts
Patch immediately- CVE-2007-3896 is a critical-severity vulnerability (CVSS 9.3 v2) affecting Internet Explorer (Microsoft).
- It is exploited in the wild, listed in Industry KEV feed since Nov 13, 2007. Public exploit code is available.
- EPSS estimates a 54% 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 it is listed as exploited in the wild.
CVSS v2
9.3
AV:N/AC:M/Au:N/C:C/I:C/A:C
EPSS (30-day exploit likelihood)
54%
Higher than 98.9% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2007-3896 brief as a PDF
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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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Nov 13, 2007 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
1 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Internet ExplorerMicrosoft | 7.0 | n/a |
Timeline
Publicly disclosed
Oct 10, 2007
Added to Industry KEV feed
Nov 13, 2007
Last updated
Apr 22, 2026
Weakness Type
- CWE-20 Improper Input Validation
References
- advisory26201
- exploitVulnCheck exploitation report
- exploitExploitDB-30645
- otherhttp://blogs.zdnet.com/security/?p=577
- other20071003 0day: mIRC pwns Windows
FAQ
Common Questions.
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 oth…
Affected: Internet Explorer (Microsoft) versions 7.0. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Nov 13, 2007.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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