SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2019-17026

Mozilla Firefox And Thunderbird Type Confusion Vulnerability

KEVHIGH 8.8EPSS 46.3%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 3 May 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

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.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
46.31% probability · 99th percentile
CISA KEV
Listed 3 November 2021 · due 3 May 2022
Weakness
CWE-843
Affected
mozilla/firefox · mozilla/thunderbird · canonical/ubuntu linux
Source
security@mozilla.org

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2019-17026

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.