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
Vendor Product Version CPE status
golang.org/x/crypto golang.org/x/crypto/ssh/agent Affected: 0 , < 0.52.0 (semver)
guessed Create a notification for this product.
Credits
NCC Group Cryptography Services, sponsored by Teleport
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.