CVE-2026-39833
Analyzed Analyzed - Analysis Complete
In-Memory Keyring ConfirmBeforeUse Constraint Bypass

Publication date: 2026-05-22

Last updated on: 2026-05-28

Assigner: Go Project

Description
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.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-05-22
Last Modified
2026-05-28
Generated
2026-06-11
AI Q&A
2026-05-22
EPSS Evaluated
2026-06-10
NVD
CVE-2026-39833
EUVD
EUVD-2026-31389
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
golang crypto to 0.52.0 (exc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-862 The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Compliance Impact

The provided information does not specify any direct impact of this vulnerability on compliance with common standards and regulations such as GDPR or HIPAA.

Executive Summary

The vulnerability in CVE-2026-39833 involves the Go programming language's ssh agent package, specifically the NewKeyring() function. This function accepted keys that had the ConfirmBeforeUse constraint but did not enforce this constraint. As a result, keys could sign data without prompting for confirmation, and the caller would not be aware that the constraint was ignored.

The issue was fixed by changing NewKeyring() to return an error when unsupported constraints like ConfirmBeforeUse are requested, preventing silent acceptance without enforcement.

Impact Analysis

This vulnerability can impact you by allowing cryptographic keys to sign data without any user confirmation, even if the keys are supposed to require confirmation before use. This could lead to unauthorized signing operations occurring silently, potentially compromising security by allowing actions that should require explicit approval to proceed without it.

Mitigation Strategies

To mitigate this vulnerability, update the golang.org/x/crypto/ssh/agent package to version v0.52.0 or later, where the issue has been fixed.

The fix ensures that the NewKeyring() function returns an error when unsupported constraints like ConfirmBeforeUse are requested, preventing keys from signing without confirmation.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-39833. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart