CVE-2017-7820
firefox: The "instanceof" operator can bypass the Xray wrapper mechanism
CVE-2017-7820 is fixed in 4 products on 1 platform, first by firefox 56.0+build6-0ubuntu1, released October 1, 2017. It is not reported as exploited. Patch Radar priority: Routine.
Routine
CVSS
n/a
Low
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0116
67th percentile
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.
Where it's fixed
| Product | Fixed in | Fix | Released |
|---|---|---|---|
| Linux | |||
| firefox · Ubuntu 18.04.6 LTS (bionic) | 56.0+build6-0ubuntu1 | firefox 56.0+build6-0ubuntu1 | Oct 1, 2017 |
| firefox-globalmenu · Ubuntu 18.04.6 LTS (bionic) | 56.0+build6-0ubuntu1 | firefox-globalmenu 56.0+build6-0ubuntu1 | Oct 1, 2017 |
| firefox-mozsymbols · Ubuntu 18.04.6 LTS (bionic) | 56.0+build6-0ubuntu1 | firefox-mozsymbols 56.0+build6-0ubuntu1 | Oct 1, 2017 |
| firefox-testsuite · Ubuntu 18.04.6 LTS (bionic) | 56.0+build6-0ubuntu1 | firefox-testsuite 56.0+build6-0ubuntu1 | Oct 1, 2017 |