Riskcovery

CVE-2026-56862

Limit handshake messages we are willing to accept post-handshake in crypto/tls

State
Published
Severity
7.5 High
Published
Aug 13, 2026
Updated
Aug 14, 2026
Reserved
Jun 23, 2026

Read the record on cve.org

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.

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCISA-ADP

Weaknesses

  • CWE-770 Allocation of Resources Without Limits or Throttling

Affected Products

ProductVersions
crypto/tlsGo standard library
  • before 1.25.13Affected
  • 1.26.0-0 to before 1.26.6Affected
  • 1.27.0-0 to before 1.27.0-rc.3Affected

References

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