How severe is CVE-2016-1955?

CVE-2016-1955 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2016-1955 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-1955?

CVE-2016-1955 primarily affects Mozilla Firefox. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-1955?

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

When was CVE-2016-1955 published?

CVE-2016-1955 was published on 2016-03-13 and last updated on 2026-06-17.

CVE-2016-1955

CVE-2016-1955 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 4.3. 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-200.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.3
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Mozilla Firefox
Published: 2016-03-13
Last modified: 2026-06-17

Description

Mozilla Firefox before 45.0 allows remote attackers to bypass the Same Origin Policy and obtain sensitive information by reading a Content Security Policy (CSP) violation report that contains path information associated with an IFRAME element.

Frequently asked questions

What is CVE-2016-1955?: Mozilla Firefox before 45.0 allows remote attackers to bypass the Same Origin Policy and obtain sensitive information by reading a Content Security Policy (CSP) violation report that contains path information associated with an IFRAME element.
How severe is CVE-2016-1955?: CVE-2016-1955 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2016-1955 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-1955?: CVE-2016-1955 primarily affects Mozilla Firefox. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-1955?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-1955 published?: CVE-2016-1955 was published on 2016-03-13 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:novell:suse_package_hub_for_suse_linux_enterprise:12:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:42.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:13.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:13.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

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