6.5
CVE-2021-38507
- EPSS 0.55%
- Published 08.12.2021 22:15:08
- Last modified 21.11.2024 06:17:16
- Source security@mozilla.org
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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.
Data is provided by the National Vulnerability Database (NVD)
Mozilla ≫ Firefox ESR Version < 91.3.0
Mozilla ≫ Thunderbird Version < 91.3.0
Debian ≫ Debian Linux Version9.0
Debian ≫ Debian Linux Version10.0
Debian ≫ Debian Linux Version11.0
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
| Type | Source | Score | Percentile |
|---|---|---|---|
| EPSS | FIRST.org | 0.55% | 0.67 |
| Source | Base Score | Exploit Score | Impact Score | Vector string |
|---|---|---|---|---|
| nvd@nist.gov | 6.5 | 2.8 | 3.6 |
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
|
| nvd@nist.gov | 4.3 | 8.6 | 2.9 |
AV:N/AC:M/Au:N/C:N/I:P/A:N
|
CWE-346 Origin Validation Error
The product does not properly verify that the source of data or communication is valid.