How severe is CVE-2012-4787?

CVE-2012-4787 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2012-4787 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 18% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-4787?

CVE-2012-4787 primarily affects Microsoft Internet Explorer. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-4787?

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-2012-4787 published?

CVE-2012-4787 was published on 2012-12-12 and last updated on 2026-06-16.

CVE-2012-4787

CVE-2012-4787 is a critical-severity vulnerability in Microsoft Internet Explorer with a CVSS 3.x base score of 9.0. Its EPSS exploit-prediction score of 18% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-399.

Key facts

Severity: Critical (CVSS 3.x base score 9.0)
CVSS v2: 9.3
EPSS exploit prediction: 18% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-399
Affected product: Microsoft Internet Explorer
Published: 2012-12-12
Last modified: 2026-06-16

Description

Use-after-free vulnerability in Microsoft Internet Explorer 9 and 10 allows remote attackers to execute arbitrary code via a crafted web site that triggers access to an object that (1) was not properly initialized or (2) is deleted, aka "Improper Ref Counting Use After Free Vulnerability."

Frequently asked questions

What is CVE-2012-4787?: Use-after-free vulnerability in Microsoft Internet Explorer 9 and 10 allows remote attackers to execute arbitrary code via a crafted web site that triggers access to an object that (1) was not properly initialized or (2) is deleted, aka "Improper Ref Counting Use After Free Vulnerability."
How severe is CVE-2012-4787?: CVE-2012-4787 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2012-4787 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 18% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-4787?: CVE-2012-4787 primarily affects Microsoft Internet Explorer. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-4787?: 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-2012-4787 published?: CVE-2012-4787 was published on 2012-12-12 and last updated on 2026-06-16.

References

Affected products (2)

cpe:2.3:a:microsoft:internet_explorer:9:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:internet_explorer:10:*:*:*:*:*:*:*

More vulnerabilities in Microsoft Internet Explorer

CVE-2014-1764 — Critical (CVSS 10.0): Microsoft Internet Explorer 7 through 11 allows remote attackers to execute arbitrary code and bypass a sandbox…
CVE-2014-1763 — Critical (CVSS 10.0): Use-after-free vulnerability in Microsoft Internet Explorer 9 through 11 allows remote attackers to execute arbitrary…
CVE-2010-1118 — Critical (CVSS 10.0): Unspecified vulnerability in Internet Explorer 8 on Microsoft Windows 7 allows remote attackers to execute arbitrary…
CVE-2009-1918 — Critical (CVSS 10.0): Microsoft Internet Explorer 5.01 SP4 and 6 SP1; Internet Explorer 6 for Windows XP SP2 and SP3 and Server 2003 SP2; and…
CVE-2009-1043 — Critical (CVSS 10.0): Unspecified vulnerability in Microsoft Internet Explorer 8 on Windows 7 allows remote attackers to execute arbitrary…
CVE-2007-3341 — Critical (CVSS 10.0): Unspecified vulnerability in the FTP implementation in Microsoft Internet Explorer allows remote attackers to "see a…

All CVEs affecting Microsoft Internet Explorer →

Other CWE-399 (Resource Management Errors) vulnerabilities

CVE-2015-8104 — Critical (CVSS 10.0): The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a…
CVE-2015-0339 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0335 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0333 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2014-4121 — Critical (CVSS 10.0): Microsoft .NET Framework 2.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2 does not properly parse internationalized…
CVE-2014-0560 — Critical (CVSS 10.0): Use-after-free vulnerability in Adobe Reader and Acrobat 10.x before 10.1.12 and 11.x before 11.0.09 on Windows and OS…

Browse all CWE-399 (Resource Management Errors) vulnerabilities →