Live › vulnerability › CVE-2019-17026
Go to dashboardMozilla Firefox and Thunderbird have a type confusion bug in the IonMonkey JIT compiler when setting array elements. An attacker who gets a user to load malicious JavaScript can likely run code in the browser or mail client.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:11 UTC, 3h before NVD. All times on this page are UTC.
Apply updates per vendor instructions.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| Mozilla Firefox and Thunderbird | vendor | – | – |
Check the installed Firefox or Thunderbird version under Help > About and compare it with the fixed release in the vendor advisory.
Update Firefox and Thunderbird to a release that includes the Mozilla fix, per the vendor instructions CISA references.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
Incorrect alias information in IonMonkey JIT compiler for setting array elements could lead to a type confusion. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Firefox ESR < 68.4.1, Thunderbird < 68.4.1, and Firefox < 72.0.1.
This page as .md · .json · in your agent: get_signal("CVE-2019-17026")
CISA KEV catalog, Creative Commons 0 · EPSS scores by FIRST, used with attribution · NVD data is provided by NIST and is public domain. Posts quoted belong to their authors.