Is CVE-2012-3993 in the CISA KEV catalog?

No. CVE-2012-3993 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2012-3993?

CVE-2012-3993 has a CVSS v2 base score of 9.3 (HIGH).

What is the EPSS score for CVE-2012-3993?

CVE-2012-3993 has an EPSS score of 42.61% (99th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2012-3993

HIGHEPSS 99th pctl

9.3

CVSS v2

NVD

Description

The Chrome Object Wrapper (COW) implementation in Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbird before 16.0, Thunderbird ESR 10.x before 10.0.8, and SeaMonkey before 2.13 does not properly interact with failures of InstallTrigger methods, which allows remote attackers to execute arbitrary JavaScript code with chrome privileges via a crafted web site, related to an "XrayWrapper pollution" issue.

CWE-269Improper Privilege Management

CVSS v2 Vector

No CVSS vector data available.

Exploit Intelligence

42.61%probability of exploitation in 30 days

99thpercentile

Very high risk: more likely to be exploited than 99% of all known CVEs.

References

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-29.