CVE-2026-78669
Public on 2026-10-08
Modified on 2026-10-10
Description
A malicious HTTP/2 peer could cause excessive CPU consumption in the client or server by opening a large number of streams and then sending many small SETTINGS frames containing SETTINGS_INITIAL_WINDOW_SIZE values.
The HTTP/2 client and server now efficiently handle changes to the initial window size (O(1) rather than O(number of streams)).
NOTE: https://www.openwall.com/lists/oss-security/2026/10/08/9
NOTE: https://github.com/golang/go/issues/81742
NOTE: Fixed by: https://github.com/golang/go/commit/1d58cdaa1069e259b60c324ec77472f09f23d92e (go1.27.2)
NOTE: Fixed by: https://github.com/golang/go/commit/6e049521882c944afc1e519a83971ec421dc2974 (go1.26.9)
The HTTP/2 client and server now efficiently handle changes to the initial window size (O(1) rather than O(number of streams)).
NOTE: https://www.openwall.com/lists/oss-security/2026/10/08/9
NOTE: https://github.com/golang/go/issues/81742
NOTE: Fixed by: https://github.com/golang/go/commit/1d58cdaa1069e259b60c324ec77472f09f23d92e (go1.27.2)
NOTE: Fixed by: https://github.com/golang/go/commit/6e049521882c944afc1e519a83971ec421dc2974 (go1.26.9)
CVSS v3 Base Score
See breakdown
Affected Packages
| Platform | Package | Release Date | Advisory | Status |
|---|---|---|---|---|
| Amazon Linux 2 - Core | golang | Pending Fix | ||
| Amazon Linux 2 - Golang1.11 Extra | golang | No Fix Planned | ||
| Amazon Linux 2 - Golang1.19 Extra | golang | No Fix Planned | ||
| Amazon Linux 2 - Golang1.9 Extra | golang | No Fix Planned | ||
| Amazon Linux 2023 | golang | Pending Fix | ||
| Amazon Linux 2027 Preview | golang | Pending Fix |
CVSS Scores
| Score Type | Score | Vector | |
|---|---|---|---|
| Amazon Linux | CVSSv3 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |