When "%2F" was present in a manifest URL, Firefox's AppCache behavior may have become confused and allowed a manifest to be served from a subdirectory. This could cause the appcache to be used to service requests for the top level directory. This vulnerability affects Firefox < 78.
https://www.mozilla.org/security/advisories/mfsa2020-24/
https://bugzilla.mozilla.org/show_bug.cgi?id=1586630
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.html
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.html
Source: MITRE
Published: 2020-07-09
Updated: 2023-01-27
Type: CWE-276
Base Score: 4.3
Vector: AV:N/AC:M/Au:N/C:N/I:P/A:N
Impact Score: 2.9
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 6.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Impact Score: 3.6
Exploitability Score: 2.8
Severity: MEDIUM