CVE-2007-3670

CVE-2007-3670 is a medium-severity vulnerability in Microsoft Internet Explorer with a CVSS 2.0 base score of 4.3. Its EPSS exploit-prediction score of 29% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-79.

Key facts

Description

Argument injection vulnerability in Microsoft Internet Explorer, when running on systems with Firefox installed and certain URIs registered, allows remote attackers to conduct cross-browser scripting attacks and execute arbitrary commands via shell metacharacters in a (1) FirefoxURL or (2) FirefoxHTML URI, which are inserted into the command line that is created when invoking firefox.exe. NOTE: it has been debated as to whether the issue is in Internet Explorer or Firefox. As of 20070711, it is CVE's opinion that IE appears to be failing to properly delimit the URL argument when invoking Firefox, and this issue could arise with other protocol handlers in IE as well. However, Mozilla has stated that it will address the issue with a "defense in depth" fix that will "prevent IE from sending Firefox malicious data."

Frequently asked questions

What is CVE-2007-3670?
Argument injection vulnerability in Microsoft Internet Explorer, when running on systems with Firefox installed and certain URIs registered, allows remote attackers to conduct cross-browser scripting attacks and execute arbitrary commands via shell metacharacters in a (1) FirefoxURL or (2) FirefoxHTML URI, which are inserted into the command line that is created when invoking firefox.exe. NOTE: it has been debated as to whether the issue is in Internet Explorer or Firefox. As of 20070711, it is CVE's opinion that IE appears to be failing to properly delimit the URL argument when invoking Firefox, and this issue could arise with other protocol handlers in IE as well. However, Mozilla has stated that it will address the issue with a "defense in depth" fix that will "prevent IE from sending Firefox malicious data."
How severe is CVE-2007-3670?
CVE-2007-3670 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2007-3670 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 29% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2007-3670?
CVE-2007-3670 primarily affects Microsoft Internet Explorer. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2007-3670?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2007-3670 published?
CVE-2007-3670 was published on 2007-07-10 and last updated on 2026-06-16.

References

Affected products (7)

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