Is CVE-2012-4207 being actively exploited?

CVE-2012-4207 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2012-4207?

CVE-2012-4207 has a CVSS 2.0 base score of 4.3 (MEDIUM).

CVE-2012-4207

MEDIUM · CVSS 4.3EPSS 2.8%EU EUVD

The HZ-GB-2312 character-set implementation in Mozilla Firefox before 17.0, Firefox ESR 10.x before 10.0.11, Thunderbird before 17.0, Thunderbird ESR 10.x before 10.0.11, and SeaMonkey before 2.14 does not properly handle a ~ (tilde) character in proximity to a chunk delimiter, which allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted document.

Key facts

CVSS score: 4.3 (v2.0)
Severity: MEDIUM
CVSS vector: AV:N/AC:M/Au:N/C:N/I:P/A:N
Weakness (CWE): CWE-79
EPSS score: 2.8% (86th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2012-4151)
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-2012-4151 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
debian / debian linux
debian / debian linux
mozilla / firefox
mozilla / seamonkey
mozilla / thunderbird
mozilla / thunderbird esr
opensuse / opensuse
opensuse / opensuse
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 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
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/2012-11/msg00021.html(Mailing List, Third Party Advisory)
http://lists.opensuse.org/opensuse-security-announce/2013-01/msg00022.html(Mailing List, Third Party Advisory)
http://lists.opensuse.org/opensuse-updates/2012-11/msg00090.html(Mailing List, Third Party Advisory)
http://lists.opensuse.org/opensuse-updates/2012-11/msg00092.html(Mailing List, Third Party Advisory)
http://lists.opensuse.org/opensuse-updates/2012-11/msg00093.html(Mailing List, Third Party Advisory)
http://osvdb.org/87587(Broken Link)
http://rhn.redhat.com/errata/RHSA-2012-1482.html(Third Party Advisory)
http://rhn.redhat.com/errata/RHSA-2012-1483.html(Third Party Advisory)
http://secunia.com/advisories/51359(Third Party Advisory)
http://secunia.com/advisories/51360(Third Party Advisory)
http://secunia.com/advisories/51369(Third Party Advisory)
http://secunia.com/advisories/51370(Third Party Advisory)
http://secunia.com/advisories/51381(Third Party Advisory)
http://secunia.com/advisories/51434(Third Party Advisory)
http://secunia.com/advisories/51439(Third Party Advisory)
http://secunia.com/advisories/51440(Third Party Advisory)
http://www.debian.org/security/2012/dsa-2583(Third Party Advisory)
http://www.debian.org/security/2012/dsa-2584(Third Party Advisory)
http://www.debian.org/security/2012/dsa-2588(Third Party Advisory)
http://www.mandriva.com/security/advisories?name=MDVSA-2012:173(Third Party Advisory)
http://www.mozilla.org/security/announce/2012/mfsa2012-101.html(Vendor Advisory)
http://www.palemoon.org/releasenotes-ng.shtml(Broken Link)
http://www.securityfocus.com/bid/56632(Third Party Advisory, VDB Entry)
http://www.ubuntu.com/usn/USN-1636-1(Third Party Advisory)
http://www.ubuntu.com/usn/USN-1638-1(Third Party Advisory)
http://www.ubuntu.com/usn/USN-1638-2(Third Party Advisory)
http://www.ubuntu.com/usn/USN-1638-3(Third Party Advisory)
https://bugzilla.mozilla.org/show_bug.cgi?id=801681(Exploit, Issue Tracking, Patch, Vendor Advisory)
https://exchange.xforce.ibmcloud.com/vulnerabilities/80179(Third Party Advisory, VDB Entry)
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16955(Third Party Advisory)

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

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