CVE-2026-39833 (GCVE-0-2026-39833)

Vulnerability from cvelistv5 – Published: 2026-05-22 02:31 – Updated: 2026-08-11 21:28
VLAI
Title
Invoking key constraints not enforced in golang.org/x/crypto/ssh/agent
Summary
The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-22 18:57 UTC
CWE
  • CWE-358 - Improperly Implemented Security Check for Standard
Assigner
References
Impacted products
Credits
NCC Group Cryptography Services, sponsored by Teleport
Show details on NVD website
To clipboard 

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