CVE-2026-56855 (High) detected in golang.org/x/crypto-v0.49.0

[mend-bolt-for-github]

CVE-2026-56855 - High Severity Vulnerability

Vulnerable Library - golang.org/x/crypto-v0.49.0

Library home page: https://proxy.golang.org/golang.org/x/crypto/@⁠v/v0.49.0.zip

Sample Path to Dependency File: /engine/go.mod

Path to vulnerable library: /home/wss-scanner/go/pkg/mod/cache/download/golang.org/x/crypto/@⁠v/v0.49.0.mod

Dependency Hierarchy:

• ❌ golang.org/x/crypto-v0.49.0 (Vulnerable Library)

Found in base branch: master

Vulnerability Details

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Publish Date: 2026-09-02

URL: CVE-2026-56855

CVSS 3 Score Details (7.5)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: None
  • Scope: Unchanged
• Impact Metrics:
  • Confidentiality Impact: None
  • Integrity Impact: None
  • Availability Impact: High

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Origin: https://pkg.go.dev/vuln/GO-2026-6355

Release Date: 2026-09-02

Fix Resolution: golang.org/x/crypto - v0.56.0,https://github.com/golang/crypto.git - v0.56.0

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