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Critical Zero-Day Response

Use this playbook to respond quickly when a new critical zero-day vulnerability is announced (e.g., widely exploited RCE or library vulnerability).

Assess Relevance​

  1. Gather basic information:
    • Affected products, versions, and configurations.
    • Known exploit vectors and mitigations.
  2. Determine whether your technology stack uses impacted software or services.

Identify Potentially Affected Assets​

Using Cloudaware:

  1. Search Cloudaware Vulnerability Scan records for:
    • CVE identifier (once available).
    • Package/library names and versions.
  2. If scanners have not yet released signatures:
    • Use CMDB and Breeze Agent data to identify where affected software may be installed.
    • Use tags, packages, and configuration data to build an initial asset list.

Create an Initiative and Tasks​

  1. Create a dedicated Zero‑Day Initiative that:
    • Describes the vulnerability, business impact, and timelines.
    • Serves as a container for related tasks and reporting.
  2. Create Remediation Tasks per OU/application or platform team, including:
    • Initial scoping and validation steps.
    • Patch or configuration changes once vendor guidance is available.

See also: Vulnerability Management Processes

Coordinate with Patch and Change Management​

  1. Work with Patch Management to:
    • Prioritize patches or configuration changes related to the zero‑day.
    • Schedule emergency maintenance windows as needed.
  2. Ensure Change Management processes are followed for high‑risk changes, but streamline approvals for emergency fixes where policy permits.

Communicate Broadly​

  1. Use collaboration and ITSM integrations to:
    • Notify affected teams, leadership, and incident response.
    • Provide regular status updates (e.g., which systems are patched, which remain exposed).
  2. Update dashboards with a dedicated view for the zero‑day Initiative.

Verify Remediation​

  1. Run targeted scans or rely on updated scanner signatures to confirm:
    • Vulnerabilities are no longer detected on patched systems.
    • No unexpected regressions appear.
  2. Update Initiative and task status to reflect remediation progress.

Document and Improve​

  1. Capture:
    • Timeline of detection, triage, remediation, and verification.
    • Decisions about exceptions and compensating controls.
  2. Use this information to:
    • Improve future zero‑day response.
    • Adjust SLAs, risk models, and patch processes as needed.