SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-5135

WebExtensions can bypass normal restrictions in some circumstances and use "browser.tabs.executeScript" to inject scripts into contexts where this should not be allowed, such as pages from other WebExtensions or unprivileged "about:" pages.

HIGH 7.5EPSS 1.53%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.53%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

WebExtensions can bypass normal restrictions in some circumstances and use "browser.tabs.executeScript" to inject scripts into contexts where this should not be allowed, such as pages from other WebExtensions or unprivileged "about:" pages. This vulnerability affects Firefox < 59.

CVSS 3.0
7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
1.53% probability · 73th percentile
CISA KEV
Not listed
Weakness
CWE-862
Affected
mozilla/firefox
Source
security@mozilla.org

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