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CVE-2020-26953
It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus making it possible to attempt a…
Medium4.3EPSS 1.3%
- Published
- Updated
- Reserved
- Assigned by
- mozilla
Description
It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus making it possible to attempt a phishing attack or otherwise confuse the user. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 1.3% · top 30% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.
Weakness
- Fullscreen could be enabled without displaying the security UI
- CWE-1021 (opens in a new tab)All about CWE-1021 and its CVEs
Affected products
- affected < 83
- affected < 78.5
- affected < 78.5
References (4)
- https://bugzilla.mozilla.org/show_bug.cgi?id=1656741 (opens in a new tab)x_refsource_MISCx_transferred
- https://www.mozilla.org/security/advisories/mfsa2020-50/ (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://www.mozilla.org/security/advisories/mfsa2020-52/ (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://www.mozilla.org/security/advisories/mfsa2020-51/ (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-26953)Record last updated .