How severe is CVE-2016-5265?

CVE-2016-5265 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2016-5265 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-5265?

CVE-2016-5265 primarily affects Mozilla Firefox. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-5265?

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

When was CVE-2016-5265 published?

CVE-2016-5265 was published on 2016-08-05 and last updated on 2026-06-17.

CVE-2016-5265

CVE-2016-5265 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 5.5. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Mozilla Firefox
Published: 2016-08-05
Last modified: 2026-06-17

Description

Mozilla Firefox before 48.0 and Firefox ESR 45.x before 45.3 allow user-assisted remote attackers to bypass the Same Origin Policy, and conduct Universal XSS (UXSS) attacks or read arbitrary files, by arranging for the presence of a crafted HTML document and a crafted shortcut file in the same local directory.

Frequently asked questions

What is CVE-2016-5265?: Mozilla Firefox before 48.0 and Firefox ESR 45.x before 45.3 allow user-assisted remote attackers to bypass the Same Origin Policy, and conduct Universal XSS (UXSS) attacks or read arbitrary files, by arranging for the presence of a crafted HTML document and a crafted shortcut file in the same local directory.
How severe is CVE-2016-5265?: CVE-2016-5265 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2016-5265 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-5265?: CVE-2016-5265 primarily affects Mozilla Firefox. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-5265?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-5265 published?: CVE-2016-5265 was published on 2016-08-05 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:o:oracle:linux:5.0:*:*:*:*:*:*:*
cpe:2.3:o:oracle:linux:6:*:*:*:*:*:*:*
cpe:2.3:o:oracle:linux:7:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:45.1.0:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:45.1.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:45.2.0:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:45.3.0:*:*:*:*:*:*:*

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