How severe is CVE-2014-1539?

CVE-2014-1539 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2014-1539 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2014-1539?

CVE-2014-1539 primarily affects Mozilla Firefox. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2014-1539?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2014-1539 published?

CVE-2014-1539 was published on 2014-06-11 and last updated on 2026-06-17.

CVE-2014-1539

CVE-2014-1539 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 5.0. 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mozilla Firefox
Published: 2014-06-11
Last modified: 2026-06-17

Description

Mozilla Firefox before 30.0 and Thunderbird through 24.6 on OS X do not ensure visibility of the cursor after interaction with a Flash object and a DIV element, which makes it easier for remote attackers to conduct clickjacking attacks via JavaScript code that produces a fake cursor image.

Frequently asked questions

What is CVE-2014-1539?: Mozilla Firefox before 30.0 and Thunderbird through 24.6 on OS X do not ensure visibility of the cursor after interaction with a Flash object and a DIV element, which makes it easier for remote attackers to conduct clickjacking attacks via JavaScript code that produces a fake cursor image.
How severe is CVE-2014-1539?: CVE-2014-1539 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2014-1539 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2014-1539?: CVE-2014-1539 primarily affects Mozilla Firefox. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2014-1539?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2014-1539 published?: CVE-2014-1539 was published on 2014-06-11 and last updated on 2026-06-17.

References

Affected products (10)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
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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