CVE-2026-39833
Invoking key constraints not enforced in golang.org/x/crypto/ssh/agent
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.
INFO
Published Date :
May 22, 2026, 4:16 a.m.
Last Modified :
May 28, 2026, 3:04 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Update the keyring implementation to enforce constraints.
- Reject unsupported constraints during keyring creation.
- Ensure confirmation prompts are honored.
- Verify cryptographic operations.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-39833.
| URL | Resource |
|---|---|
| https://go.dev/cl/778640 | Issue Tracking |
| https://go.dev/cl/778641 | Issue Tracking |
| https://go.dev/issue/79436 | Issue Tracking |
| https://groups.google.com/g/golang-announce/c/a082jnz-LvI | Mailing List |
| https://pkg.go.dev/vuln/GO-2026-5005 | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-39833 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-39833
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-39833 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-39833 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 28, 2026
Action Type Old Value New Value Added CWE CWE-862 Added CPE Configuration OR *cpe:2.3:a:golang:crypto:*:*:*:*:*:go:*:* versions up to (excluding) 0.52.0 Added Reference Type Go Project: https://go.dev/cl/778640 Types: Issue Tracking Added Reference Type Go Project: https://go.dev/cl/778641 Types: Issue Tracking Added Reference Type Go Project: https://go.dev/issue/79436 Types: Issue Tracking Added Reference Type Go Project: https://groups.google.com/g/golang-announce/c/a082jnz-LvI Types: Mailing List Added Reference Type Go Project: https://pkg.go.dev/vuln/GO-2026-5005 Types: Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
May. 22, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N -
New CVE Received by [email protected]
May. 22, 2026
Action Type Old Value New Value Added 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. Added Reference https://go.dev/cl/778640 Added Reference https://go.dev/cl/778641 Added Reference https://go.dev/issue/79436 Added Reference https://groups.google.com/g/golang-announce/c/a082jnz-LvI Added Reference https://pkg.go.dev/vuln/GO-2026-5005