Is there a public exploit for CVE-2026-39833?

No public exploit for CVE-2026-39833 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-39833?

CVE-2026-39833 scores CVSS 9.1 (v3.1), rated critical. EPSS puts the chance of exploitation in the next 30 days at 0.47%.

What does CVE-2026-39833 affect?

CVE-2026-39833 affects golang.org/x/crypto golang.org/x/crypto/ssh/agent.

9.1 Critical

The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it.

CVE-2026-39833

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.

Assessment

CVSS: 9.1 (v3.1)
Severity: Critical
EPSS: 0.47% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 22 May 2026
Last updated: 11 August 2026
Affected: golang.org/x/crypto · golang.org/x/crypto/ssh/agent
Weakness: CWE-862
Assigner: security@golang.org

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

At the source

References

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