How severe is CVE-2013-0764?

CVE-2013-0764 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2013-0764 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-0764?

CVE-2013-0764 primarily affects Mozilla Firefox. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2013-0764?

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-2013-0764 published?

CVE-2013-0764 was published on 2013-01-13 and last updated on 2026-06-16.

CVE-2013-0764

CVE-2013-0764 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 9.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-326.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-326
Affected product: Mozilla Firefox
Published: 2013-01-13
Last modified: 2026-06-16

Description

The nsSOCKSSocketInfo::ConnectToProxy function in Mozilla Firefox before 18.0, Firefox ESR 17.x before 17.0.2, Thunderbird before 17.0.2, Thunderbird ESR 17.x before 17.0.2, and SeaMonkey before 2.15 does not ensure thread safety for SSL sessions, which allows remote attackers to execute arbitrary code via crafted data, as demonstrated by e-mail message data.

Frequently asked questions

What is CVE-2013-0764?: The nsSOCKSSocketInfo::ConnectToProxy function in Mozilla Firefox before 18.0, Firefox ESR 17.x before 17.0.2, Thunderbird before 17.0.2, Thunderbird ESR 17.x before 17.0.2, and SeaMonkey before 2.15 does not ensure thread safety for SSL sessions, which allows remote attackers to execute arbitrary code via crafted data, as demonstrated by e-mail message data.
How severe is CVE-2013-0764?: CVE-2013-0764 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2013-0764 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-0764?: CVE-2013-0764 primarily affects Mozilla Firefox. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-0764?: 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-2013-0764 published?: CVE-2013-0764 was published on 2013-01-13 and last updated on 2026-06-16.

References

Affected products (17)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:seamonkey:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird_esr:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:11.4:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:12.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:12.2:*:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_desktop:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_desktop:11:sp2:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:10:sp4:*:*:*:*:*:*
cpe:2.3:o:suse:linux_enterprise_server:11:sp2:*:*:*:-:*:*
cpe:2.3:o:suse:linux_enterprise_server:11:sp2:*:*:*:vmware:*:*
cpe:2.3:o:suse:linux_enterprise_software_development_kit:11:sp2:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:10.04:*:*:*:-:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:11.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.10:*:*:*:*:*:*:*

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