CVE-2026-56862 (GCVE-0-2026-56862)

Vulnerability from cvelistv5 – Published: 2026-08-13 21:58 – Updated: 2026-08-14 15:29
VLAI
Title
Limit handshake messages we are willing to accept post-handshake in crypto/tls
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-14 15:27 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version CPE status
Go standard library crypto/tls Affected: 0 , < 1.25.13 (semver)
Affected: 1.26.0-0 , < 1.26.6 (semver)
Affected: 1.27.0-0 , < 1.27.0-rc.3 (semver)
guessed Create a notification for this product.
Credits
Qi Deng of Aurascape.ai
Show details on NVD website
To clipboard 

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          "url": "https://pkg.go.dev/vuln/GO-2026-6090"
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}



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