SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-35111

While web content cannot navigate to such URLs, a user opening View Source could have inadvertently leaked their IP address.

MEDIUM 4.3EPSS 1.42%

Does this matter?

Lower severity and a low EPSS score (1.42%). Track it; it rarely justifies an emergency change on its own.

Description

When an extension with the proxy permission registered to receive <all_urls>, the proxy.onRequest callback was not triggered for view-source URLs. While web content cannot navigate to such URLs, a user opening View Source could have inadvertently leaked their IP address. This vulnerability affects Firefox < 84, Thunderbird < 78.6, and Firefox ESR < 78.6.

CVSS 3.1
4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
EPSS
1.42% probability · 71th percentile
CISA KEV
Not listed
Affected
mozilla/firefox · mozilla/firefox esr · mozilla/thunderbird
Source
security@mozilla.org

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