7.5
High
CVE-2026-56862 Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a handshake has…
Description
Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a handshake has been completed or not. As a result, a malicious client can keep sending KeyUpdate messages to force the server to keep performing key derivation operations indefinitely.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| crypto/tls 1.27 | earliest → < 1.27.0-rc.3 | 1.27.0-rc.3 |
| crypto/tls 1.26 | 1.26.0-0 → < 1.26.6 | 1.26.6 |
| crypto/tls 1.25 | earliest → < 1.25.13 | 1.25.13 |
References
- go.dev go.dev
- go.dev go.dev
- groups.google.com groups.google.com
- pkg.go.dev pkg.go.dev
Timeline
- Published
- Last modified
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