CVE-2021-38507
CVSS v3.1
6.5 (Medium)
CVSS v2.0
4.3 (Medium)
EPSS
0.50 % (77th)
Affected Products
4
Advisories
31
The Opportunistic Encryption feature of HTTP2 (RFC 8164) allows a connection to be transparently upgraded to TLS while retaining the visual properties of an HTTP connection, including being same-origin with unencrypted connections on port 80. However, if a second encrypted port on the same IP address (e.g. port 8443) did not opt-in to opportunistic encryption; a network attacker could forward a connection from the browser to port 443 to port 8443, causing the browser to treat the content of port 8443 as same-origin with HTTP. This was resolved by disabling the Opportunistic Encryption feature, which had low usage. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.
Weaknesses
- CWE-346
- Origin Validation Error
- CVE Status
- PUBLISHED
- CNA
- Mozilla Corporation
- Published Date
-
2021-12-08 22:15:08
(2 years ago) - Updated Date
-
2022-12-09 15:54:38
(21 months ago)
Affected Products
Loading...
Loading...
Loading...
Configuration #1
|
Configuration #2
|
Loading...
Loading...
Loading...
Loading...
Loading...
Loading...
Loading...
Loading...