SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2019-11711

If pages on different subdomains ever cooperatively use document.domain, then either page can abuse this to inject script into arbitrary pages on the other subdomain, even those that did not use document.domain to relax their origin security.

HIGH 8.8EPSS 1.63%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.63%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

When an inner window is reused, it does not consider the use of document.domain for cross-origin protections. If pages on different subdomains ever cooperatively use document.domain, then either page can abuse this to inject script into arbitrary pages on the other subdomain, even those that did not use document.domain to relax their origin security. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
1.63% probability · 75th percentile
CISA KEV
Not listed
Affected
mozilla/firefox · mozilla/thunderbird · debian/debian linux
Source
security@mozilla.org

References

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