How severe is CVE-2019-11741?

CVE-2019-11741 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2019-11741 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-11741?

CVE-2019-11741 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-11741?

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

When was CVE-2019-11741 published?

CVE-2019-11741 was published on 2019-09-27 and last updated on 2026-06-17.

CVE-2019-11741

CVE-2019-11741 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 6.1. 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 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Mozilla Firefox
Published: 2019-09-27
Last modified: 2026-06-17

Description

A compromised sandboxed content process can perform a Universal Cross-site Scripting (UXSS) attack on content from any site it can cause to be loaded in the same process. Because addons.mozilla.org and accounts.firefox.com have close ties to the Firefox product, malicious manipulation of these sites within the browser can potentially be used to modify a user's Firefox configuration. These two sites will now be isolated into their own process and not allowed to be loaded in a standard content process. This vulnerability affects Firefox < 69.

Frequently asked questions

What is CVE-2019-11741?: A compromised sandboxed content process can perform a Universal Cross-site Scripting (UXSS) attack on content from any site it can cause to be loaded in the same process. Because addons.mozilla.org and accounts.firefox.com have close ties to the Firefox product, malicious manipulation of these sites within the browser can potentially be used to modify a user's Firefox configuration. These two sites will now be isolated into their own process and not allowed to be loaded in a standard content process. This vulnerability affects Firefox < 69.
How severe is CVE-2019-11741?: CVE-2019-11741 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2019-11741 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-11741?: CVE-2019-11741 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-11741?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-11741 published?: CVE-2019-11741 was published on 2019-09-27 and last updated on 2026-06-17.

References

Affected products (1)

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

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