The "instanceof" operator can bypass the Xray wrapper mechanism
Published Jun 11, 2018
5.3
MEDIUMCVSS 3.0
EPSS 1.19%
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.
Affected products
-
- Version unspecifiedStatusaffectedConstraints<56
- Version
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
AV:N/AC:L/Au:N/C:N/I:P/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Table of values (11 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 1.19% (0.01188) | 66.76th | v5 (v2026.06.15) |
| Sep 20, 2026 | 1.19% (0.01188) | 66.50th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.48% (0.00484) | 76.19th | v3 (v2023.03.01) |
| Feb 22, 2024 | 0.48% (0.00484) | 75.30th | v3 (v2023.03.01) |
| Nov 2, 2023 | 0.48% (0.00484) | 73.30th | v3 (v2023.03.01) |
| Sep 3, 2023 | 0.58% (0.00580) | 75.32th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.75% (0.00750) | 78.09th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.02% (0.01018) | 40.69th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.02% (0.01018) | 19.50th | v2 (v2022.01.01) |
| Feb 3, 2022 | 1.10% (0.01105) | 29.18th | v5 (v2026.06.15) |
| Apr 14, 2021 | 1.10% (0.01105) | 0.00th | v1 |
No CWE recorded.
References (4)
- http://www.securityfocus.com/bid/101057 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1039465 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1378207 x_refsource_CONFIRMExploitIssue Tracking
- https://www.mozilla.org/security/advisories/mfsa2017-21/ x_refsource_CONFIRMVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| http://www.securityfocus.com/bid/101057 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| http://www.securitytracker.com/id/1039465 | vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry | |
| https://bugzilla.mozilla.org/show_bug.cgi?id=1378207 | x_refsource_CONFIRMExploitIssue Tracking | |
| https://www.mozilla.org/security/advisories/mfsa2017-21/ | x_refsource_CONFIRMVendor Advisory |
Change history (0)
No recorded changes yet.