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CVE-2020-6809
When a Web Extension had the all-urls permission and made a fetch request with a mode set to 'same-origin', it was possible for the Web…
High7.5EPSS 1.5%
- Published
- Updated
- Reserved
- Assigned by
- mozilla
Description
When a Web Extension had the all-urls permission and made a fetch request with a mode set to 'same-origin', it was possible for the Web Extension to read local files. This vulnerability affects Firefox < 74.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 1.5% · top 26% 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: High 7.5.
Weakness
- Web Extensions with the all-urls permission could access local files
Affected products
References (2)
- https://www.mozilla.org/security/advisories/mfsa2020-08/ (opens in a new tab)x_refsource_MISCx_transferred
- https://bugzilla.mozilla.org/show_bug.cgi?id=1420296 (opens in a new tab)x_refsource_MISCx_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-2020-6809)Record last updated .