Patch Tuesday · November 2025

November 2025 Patch Tuesday: what UK businesses need to know.

November 2025's release was led by browser updates, a cluster of Office issues, and one Windows vulnerability reported as actively exploited at time of disclosure.

Executive summary

Browser, Office and one exploited Windows vulnerability.

November 2025's release was led by browser updates, a cluster of Office issues, and one Windows vulnerability reported as actively exploited at time of disclosure.

  • Risk theme: Actively exploited Windows EoP
  • Risk theme: Edge / Chromium updates
  • Risk theme: Office RTF parser flaw
  • Risk theme: Visual Studio supply-chain risk
Vulnerabilities remediated

The issues that move the needle this month.

We have focused on the categories with realistic exploitation paths for UK SMEs and regulated firms. Always cross-check with Microsoft's Security Update Guide and your own asset inventory before deployment.

Windows elevation of privilege (exploited)

Reported as actively exploited in the wild. Prioritise above the rest of the release.

Edge / Chromium engine updates

Bundled with upstream Chromium fixes for memory corruption issues — Edge updates should always follow within the maintenance window.

Office RTF parser flaw

RTF documents continue to be a useful attacker primitive because they bypass some macro-blocking controls.

Visual Studio remote code execution

Relevant to development teams — supply-chain risk if developer workstations are not patched on the same cycle as production endpoints.

Affected systems

Where the risk lives.

  • Windows 10, 11 and Server
  • Microsoft Edge
  • Microsoft Office
  • Visual Studio (developer workstations)
Known deployment issues

What to watch for when rolling out.

  • Edge update required closing all windows before applying — sessions persisted otherwise.
  • Some Office RTF templates needed re-saving after the parser update.
Pros of deploying
  • Closes an actively exploited issue — material reduction in real-world risk.
  • Aligns developer toolchain with the rest of the estate.
Cons / trade-offs
  • Browser session loss can frustrate users if not communicated.
  • Developer machines often sit outside standard MDM — easy to miss.
Hints & tips for a successful deployment

How experienced teams roll these out without drama.

  • Treat the exploited CVE as same-week, regardless of severity rating.
  • Bring developer workstations into the same patching ring as the wider business.
  • Communicate Edge restart requirement in advance to avoid lost work.
How Secure Chain helps

Advice, guidance, or full remediation — your call.

Whether you want a second pair of eyes on this month's release or you would rather hand the entire patching cycle to us, Secure Chain Technology Group can support at any level of involvement.

  • Advisory: a prioritised briefing mapped to your estate and risk appetite, with recommended rollout rings.
  • Guided deployment: we work alongside your IT team — test plans, rollback procedures and change-management evidence.
  • Fully managed remediation: we deploy, validate and report on every patch through our Vulnerability Management-as-a-Service (VMaaS) and Patch Management services.
  • Compliance evidence: reporting aligned to Cyber Essentials Plus, ISO 27001 and DSPT requirements.
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Always verify against the official Microsoft Security Update Guide and your own asset inventory before deployment.