SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2019-9793

This vulnerability could allow an attacker to create an arbitrary value in compiled JavaScript, for which the range analysis will infer a fully controlled, incorrect range in circumstances where users have explicitly disabled Spectre mitigations. *Note:…

MEDIUM 5.9EPSS 1.63%

Does this matter?

Lower severity and a low EPSS score (1.63%). Track it; it rarely justifies an emergency change on its own.

Description

A mechanism was discovered that removes some bounds checking for string, array, or typed array accesses if Spectre mitigations have been disabled. This vulnerability could allow an attacker to create an arbitrary value in compiled JavaScript, for which the range analysis will infer a fully controlled, incorrect range in circumstances where users have explicitly disabled Spectre mitigations. *Note: Spectre mitigations are currently enabled for all users by default settings.*. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

CVSS 3.0
5.9 MEDIUMCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
1.63% probability · 75th percentile
CISA KEV
Not listed
Weakness
CWE-119
Affected
mozilla/firefox · mozilla/firefox esr · mozilla/thunderbird
Source
security@mozilla.org

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