CVE-2017-7820

MediumCVSS 5.3/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.0 5.3/10CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected software

No affected versions have been published.

Timeline

Published: Jun 11, 2018
Last modified: Jun 17, 2026
NVD status: Modified

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