8.8
High
CVE-2019-17026 Mozilla Firefox And Thunderbird Type Confusion Vulnerability
Active exploitation observed
· CISA KEV catalogue
Required action
Apply updates per vendor instructions.
Ransomware campaigns
Not observed so far
Weakness
CWE-843
Description
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.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox ESR 68.4 | earliest → < 68.4.1 | 68.4.1 |
| Thunderbird 68.4 | earliest → < 68.4.1 | 68.4.1 |
| Firefox 72.0 | earliest → < 72.0.1 | 72.0.1 |
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