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Vulnerability record · CVE-2026-39833 · published 22 May 2026

CVE-2026-39833: Golang crypto missing authorization vulnerability

Golang · Crypto

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.

9.1 CVSS 3.1 Critical EPSS 0.49% · top 60.5% CWE-862 · Missing authorization
9.1CVSS 3.1 base score
0.49%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
11 Aug 2026Last modified by NVD

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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://go.dev/cl/778642
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

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-39833), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.