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CVE-2012-4203

MEDIUM · CVSS 6.8EPSS 3.3%EU EUVD

The New Tab page in Mozilla Firefox before 17.0 uses a privileged context for execution of JavaScript code by bookmarklets, which allows user-assisted remote attackers to run arbitrary programs by leveraging a javascript: URL in a bookmark.

Key facts

CVSS score
6.8 (v2.0)
Severity
MEDIUM
CVSS vector
AV:N/AC:M/Au:N/C:P/I:P/A:P
Weakness (CWE)
CWE-264
EPSS score
3.3% (88th percentile)
In CISA KEV
No
In EU EUVD
Yes (EUVD-2012-4147)
Published
November 21, 2012
NVD last modified
June 16, 2026
Status
Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2012-4147 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.

View on the EU Vulnerability Database

Affected products

  • mozilla / firefox
  • mozilla / firefox
  • mozilla / firefox
  • mozilla / firefox
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  • mozilla / firefox
  • mozilla / firefox
  • mozilla / firefox
  • mozilla / firefox

and 121 more…

References

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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