MEDIUM · 5.3

CVE-2017-7820

The "instanceof" operator can bypass the Xray wrapper mechanism. When called on web content from the browser itself or an extension the web content can provide its own result for that operator, possib...

Vulnerability Description

The "instanceof" operator can bypass the Xray wrapper mechanism. When called on web content from the browser itself or an extension the web content can provide its own result for that operator, possibly tricking the browser or extension into mishandling the element. This vulnerability affects Firefox < 56.

CVSS Score

5.3

MEDIUM

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE

Affected Products

VendorProductVersions
MozillaFirefox<= 55.0.3

References

FAQ

What is CVE-2017-7820?

CVE-2017-7820 is a vulnerability with a CVSS score of 5.3 (MEDIUM). The "instanceof" operator can bypass the Xray wrapper mechanism. When called on web content from the browser itself or an extension the web content can provide its own result for that operator, possib...

How severe is CVE-2017-7820?

CVE-2017-7820 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2017-7820?

Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox.