← Back to results
Vulnerability record · public intelligence
CVE-2026-56854
HIGH

Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh

Published Aug 28, 2026 · Updated Nov 3, 2026

Severity · CVSSHIGH · Not scored
Known exploitationNot listed
EPSS / likelihood0.44%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
MEDIUM
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. go.dev ↗
  2. go.dev ↗
  3. pkg.go.dev ↗

Record history

Published Aug 28, 2026 · Last refreshed Nov 3, 2026