CVE-2020-15655
A redirected HTTP request which is observed or modified through a web extension could bypass existing CORS checks, leading to potential disclosure of cross-origin information.
Does this matter?
Lower severity and a low EPSS score (1.52%). Track it; it rarely justifies an emergency change on its own.
Description
A redirected HTTP request which is observed or modified through a web extension could bypass existing CORS checks, leading to potential disclosure of cross-origin information. This vulnerability affects Firefox ESR < 78.1, Firefox < 79, and Thunderbird < 78.1.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- EPSS
- 1.52% probability · 74th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- mozilla/firefox · mozilla/firefox esr · mozilla/thunderbird · opensuse/leap · canonical/ubuntu linux
- Source
- security@mozilla.org
EPSS 1.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00025.htmlMailing List, Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1645204Issue Tracking, Vendor Advisory
- https://usn.ubuntu.com/4443-1/Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-30/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-32/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-33/Vendor Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00025.htmlMailing List, Third Party Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1645204Issue Tracking, Vendor Advisory
- https://usn.ubuntu.com/4443-1/Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-30/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-32/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-33/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.