SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2019-9794

A vulnerability was discovered where specific command line arguments are not properly discarded during Firefox invocation as a shell handler for URLs.

CRITICAL 9.8EPSS 1.77%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.77%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A vulnerability was discovered where specific command line arguments are not properly discarded during Firefox invocation as a shell handler for URLs. This could be used to retrieve and execute files whose location is supplied through these command line arguments if Firefox is configured as the default URI handler for a given URI scheme in third party applications and these applications insufficiently sanitize URL data. *Note: This issue only affects Windows operating systems. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

CVSS 3.0
9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.77% probability · 77th percentile
CISA KEV
Not listed
Weakness
CWE-88
Affected
mozilla/firefox · mozilla/thunderbird
Source
security@mozilla.org

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