Is CVE-2012-3976 being actively exploited?

CVE-2012-3976 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2012-3976?

CVE-2012-3976 has a CVSS 2.0 base score of 4.3 (MEDIUM).

CVE-2012-3976

MEDIUM · CVSS 4.3EPSS 1.8%EU EUVD

Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, and SeaMonkey before 2.12 do not properly handle onLocationChange events during navigation between different https sites, which allows remote attackers to spoof the X.509 certificate information in the address bar via a crafted web page.

Key facts

CVSS score: 4.3 (v2.0)
Severity: MEDIUM
CVSS vector: AV:N/AC:M/Au:N/C:P/I:N/A:N
Weakness (CWE): CWE-200
EPSS score: 1.8% (78th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2012-3920)
Published: August 29, 2012
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2012-3920 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.

View on the EU Vulnerability Database

Affected products

canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
mozilla / firefox
mozilla / seamonkey
opensuse / opensuse
redhat / enterprise linux desktop
redhat / enterprise linux desktop
redhat / enterprise linux eus
redhat / enterprise linux server
redhat / enterprise linux server
redhat / enterprise linux server eus
redhat / enterprise linux workstation
redhat / enterprise linux workstation
suse / linux enterprise desktop
suse / linux enterprise desktop
suse / linux enterprise server
suse / linux enterprise server
suse / linux enterprise server
suse / linux enterprise software development kit

Certified products that may be affected

3 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

SUSE Linux Enterprise Server 11 Service Pack 2 on IBM System z - SUSE Linux Products Gmbh - Common Criteria BSI-DSZ-CC-0852-2013 - archived
SUSE Linux Enterprise Server 11 Service Pack 2 including KVM virtualization - SUSE Linux Products Gmbh - Common Criteria BSI-DSZ-CC-0787-2013 - archived
Red Hat Enterprise Linux 5 OpenSSH-Server Cryptographic Module - Red Hat®, Inc. - FIPS 140 1384 - historical

References

http://lists.opensuse.org/opensuse-security-announce/2012-08/msg00028.html(Mailing List, Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2012-09/msg00011.html(Mailing List, Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2012-09/msg00014.html(Mailing List, Third Party Advisory)
http://rhn.redhat.com/errata/RHSA-2012-1210.html(Third Party Advisory)
http://www.mozilla.org/security/announce/2012/mfsa2012-69.html(Vendor Advisory)
http://www.securityfocus.com/bid/55313(Third Party Advisory, VDB Entry)
http://www.ubuntu.com/usn/USN-1548-1(Third Party Advisory)
http://www.ubuntu.com/usn/USN-1548-2(Third Party Advisory)
http://www.xerox.com/download/security/security-bulletin/16287-4d6b7b0c81f7b/cert_XRX13-003_v1.0.pdf(Third Party Advisory)
https://bugzilla.mozilla.org/show_bug.cgi?id=768568(Issue Tracking, Vendor Advisory)
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16060(Third Party Advisory)

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

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