CVE-2019-11691

Name: CVE-2019-11691
Creator: NVD / NIST
Published: 2019-07-23T14:15:13.903+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 1.61%

Last modified Jun 17, 2026

CVE-2019-11691 is a vulnerability of currently unknown severity. A use-after-free vulnerability can occur when working with XMLHttpRequest (XHR) in an event loop, causing the XHR main thread to be called after it has been freed. This results in a potentially exploitable crash. EPSS estimates a 1.61% chance of exploitation in the next 30 days.

Description

A use-after-free vulnerability can occur when working with XMLHttpRequest (XHR) in an event loop, causing the XHR main thread to be called after it has been freed. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

Metrics

EPSS Probability

1.61%

72.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-416

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 67.0
Mozilla	Firefox Esr	< 60.7
Mozilla	Thunderbird	< 60.7

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1542465Issue Tracking, Permissions Required, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2019-13/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2019-14/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2019-15/Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1542465Issue Tracking, Permissions Required, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2019-13/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2019-14/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2019-15/Vendor Advisory

Timeline

Published: Jul 23, 2019
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-11691?

How severe is CVE-2019-11691?

Severity scoring for CVE-2019-11691 is pending analysis. The EPSS model estimates a 1.61% probability of exploitation in the next 30 days.

How do I fix CVE-2019-11691?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2019-11691?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST