Answer in brief
CVE-2026-56854 records a High severity (CVSS 7.5) vulnerability in Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh. The current sources do not mark it as known exploited. The current feed maps golang.org/x/crypto/golang.org/x/crypto/ssh (generic), golang.org/x/crypto (go). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps golang.org/x/crypto/golang.org/x/crypto/ssh (generic), golang.org/x/crypto (go). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| golang.org/x/crypto/golang.org/x/crypto/sshgeneric | >=0 <0.55.0 | 0.55.0 |
| golang.org/x/cryptogo | >=0 <0.55.0 | 0.55.0 |
Published upstream
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 28, 2026
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.
Quoted source text, attributed separately from HOL analysis.