How severe is CVE-2016-9901?

CVE-2016-9901 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2016-9901 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-2016-9901?

CVE-2016-9901 primarily affects Mozilla Firefox. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-9901?

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-2016-9901 published?

CVE-2016-9901 was published on 2018-06-11 and last updated on 2026-06-17.

CVE-2016-9901

CVE-2016-9901 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mozilla Firefox
Published: 2018-06-11
Last modified: 2026-06-17

Description

HTML tags received from the Pocket server will be processed without sanitization and any JavaScript code executed will be run in the "about:pocket-saved" (unprivileged) page, giving it access to Pocket's messaging API through HTML injection. This vulnerability affects Firefox ESR < 45.6 and Firefox < 50.1.

Frequently asked questions

What is CVE-2016-9901?: HTML tags received from the Pocket server will be processed without sanitization and any JavaScript code executed will be run in the "about:pocket-saved" (unprivileged) page, giving it access to Pocket's messaging API through HTML injection. This vulnerability affects Firefox ESR < 45.6 and Firefox < 50.1.
How severe is CVE-2016-9901?: CVE-2016-9901 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2016-9901 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-2016-9901?: CVE-2016-9901 primarily affects Mozilla Firefox. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-9901?: 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-2016-9901 published?: CVE-2016-9901 was published on 2018-06-11 and last updated on 2026-06-17.

References

Affected products (15)

cpe:2.3:o:redhat:enterprise_linux_aus:7.3:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_aus:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:5.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:7.3:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:7.5:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:5.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:5.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

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