SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-26958

Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker.

MEDIUM 6.1EPSS 1.36%

Does this matter?

Lower severity and a low EPSS score (1.36%). Track it; it rarely justifies an emergency change on its own.

Description

Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker. This could lead to a cross-site script inclusion vulnerability, or a Content Security Policy bypass. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

CVSS 3.1
6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS
1.36% probability · 70th percentile
CISA KEV
Not listed
Weakness
CWE-79
Affected
mozilla/firefox · mozilla/firefox esr · mozilla/thunderbird
Source
security@mozilla.org

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