How severe is CVE-2014-1551?

CVE-2014-1551 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2014-1551 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2014-1551?

CVE-2014-1551 primarily affects Mozilla Firefox. In total, 20 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2014-1551?

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-2014-1551 published?

CVE-2014-1551 was published on 2014-07-23 and last updated on 2026-06-17.

CVE-2014-1551

CVE-2014-1551 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mozilla Firefox
Published: 2014-07-23
Last modified: 2026-06-17

Description

Use-after-free vulnerability in the FontTableRec destructor in Mozilla Firefox before 31.0, Firefox ESR 24.x before 24.7, and Thunderbird before 24.7 on Windows allows remote attackers to execute arbitrary code via crafted use of fonts in MathML content, leading to improper handling of a DirectWrite font-face object.

Frequently asked questions

What is CVE-2014-1551?: Use-after-free vulnerability in the FontTableRec destructor in Mozilla Firefox before 31.0, Firefox ESR 24.x before 24.7, and Thunderbird before 24.7 on Windows allows remote attackers to execute arbitrary code via crafted use of fonts in MathML content, leading to improper handling of a DirectWrite font-face object.
How severe is CVE-2014-1551?: CVE-2014-1551 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2014-1551 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2014-1551?: CVE-2014-1551 primarily affects Mozilla Firefox. In total, 20 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2014-1551?: 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-2014-1551 published?: CVE-2014-1551 was published on 2014-07-23 and last updated on 2026-06-17.

References

Affected products (20)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:24.0:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:24.0.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:24.0.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:24.1.0:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:24.1.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox_esr:24.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox_esr:24.3:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox_esr:24.4:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox_esr:24.5:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox_esr:24.6:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:24.0:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:24.0.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:24.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:24.1.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:24.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:24.3:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:24.4:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:24.5:*:*:*:*:*:*:*

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