AI-Powered Patch Tuesday Triage: December 2025

57 Microsoft CVEs in a single month isn’t unusual anymore. What’s unusual is the mix: one actively exploited zero-day, two publicly disclosed zero-days, and two Critical Office RCEs—all landing in December, when a lot of teams are running on holiday staffing and change-freeze politics.

Here’s the stance I’ll take: most organizations still treat Patch Tuesday as an IT calendar event, not a security race. That gap matters because adversaries don’t wait for your maintenance window—especially when an elevation of privilege (EoP) bug can turn a foothold into full control, or when Office preview-pane RCEs can light up endpoints from a single email.

This post is part of our AI in Cybersecurity series, and December 2025 is a clean example of why AI belongs in the patching conversation. Not as hype—as a practical way to detect exploitation early, prioritize what matters, and reduce the time you stay exposed.

What December 2025 Patch Tuesday really tells us

December’s release is a reminder that volume isn’t the real problem—prioritization is. Microsoft addressed 57 vulnerabilities, and the risk distribution points to where attackers keep investing.

The biggest buckets this month:

• Elevation of privilege: 28 patches (49%)
• Remote code execution (RCE): 19 patches (34%)
• Information disclosure: 4 patches (7%)

Windows got the most fixes (38), followed by Office (14). If you’re thinking “we’ll patch servers first,” you’re not wrong—but December’s Office items are a sharp reminder that client-side exposure is still a primary breach path, especially when the preview pane is involved.

Why EoP dominates—and why that’s a bad sign

EoP vulnerabilities showing up as the largest category is not random. Attack chains increasingly look like this:

1. Initial access (phish, stolen creds, exposed service)
2. Local execution on a workstation or server
3. EoP to SYSTEM
4. Credential dumping, lateral movement, domain impact

EoP is the accelerator pedal. If you can only patch one class “fast,” patch the ones that convert minor access into major control.

The actively exploited zero-day: why “local” still means urgent

The headline issue this month is CVE-2025-62221, an Important Windows vulnerability in the Cloud Files Mini Filter Driver with a CVSS 7.8. It’s an elevation of privilege flaw (use-after-free) that lets an authenticated attacker go from low privilege to SYSTEM.

People sometimes downplay “local” vulnerabilities. That’s a mistake.

Here’s why:

• Local access isn’t rare. A phish that drops a lightweight payload, a compromised browser session, or a malicious installer can all create “local” execution.
• No user interaction + low complexity means exploitation can be automated once an attacker has a foothold.
• SYSTEM-level control is where endpoint protections get disabled, credentials get harvested, and persistence becomes durable.

A “local” SYSTEM EoP is how small intrusions become expensive incidents.

Where AI-driven threat detection fits (before you can patch everything)

Patching is the fix. AI-driven detection is the buffer when reality hits—endpoints are off-network, change windows slip, and exceptions pile up.

In practical terms, AI helps by:

• Spotting post-exploitation behavior that often follows EoP (token manipulation, suspicious driver interactions, unusual privilege transitions)
• Correlating weak signals across endpoints (one machine doing something odd is noise; 30 machines doing it is a campaign)
• Prioritizing exposure using live telemetry (assets showing exploit-like behavior rise to the top immediately)

If you’re relying only on “patch status,” you’re blind to whether attackers are already using the flaw.

Two publicly disclosed zero-days: the new reality of “weaponizable soon”

December also includes two publicly disclosed Important zero-days—not actively exploited (as reported), but publicly known. That changes the timeline.

Once a vulnerability is publicly described, defenders and attackers get the same gift. The difference is attackers often operationalize faster.

Copilot for JetBrains: when developer tools become execution paths

CVE-2025-64671 is an Important RCE in GitHub Copilot for JetBrains (CVSS 8.4) involving command injection. It’s described as exploitable via malicious cross-prompt injection in untrusted files or MCP servers, especially where terminal auto-approve settings allow command execution workflows.

This matters because developer environments are unusually privileged:

• They often have access to source code, build secrets, signing keys
• They interact with CI/CD systems and cloud consoles
• They’re full of automation hooks (exactly what command injection feeds on)

AI in cybersecurity isn’t just about detecting malware. It’s about controlling AI-enabled workflows so “helpful automation” doesn’t become “approved execution.”

My opinion: if you’re rolling out AI assistants in IDEs, you need security policy as part of the rollout checklist—not after the first incident.

PowerShell command injection: still a favorite for a reason

CVE-2025-54100 is an Important PowerShell RCE (CVSS 7.8) via command injection. It requires user interaction (often social engineering) but no privileges.

PowerShell is attractive because it’s everywhere, powerful, and blends into normal admin activity. If you’re defending Windows fleets, you should assume:

• Attackers will attempt PowerShell-based execution paths
• “Looks like admin work” is part of the camouflage

AI-driven analytics can help by modeling “normal” PowerShell usage patterns and surfacing anomalies like:

• Unusual parent/child process chains for PowerShell
• Suspicious argument patterns (encoded commands, obfuscated strings)
• PowerShell launched from Office or browser processes

Two Critical Office RCEs: preview pane is still a liability

The two Critical vulnerabilities are CVE-2025-62554 and CVE-2025-62557—both Office RCEs with CVSS 8.4. One involves type confusion, the other a use-after-free condition.

The operational takeaway is blunt: email remains an execution channel, and Office preview features remain a consistent weak point.

The worst-case scenario described is what makes these scary:

• No authentication required
• No user interaction in the worst case
• Triggerable via malicious emails or links, with preview pane as a vector

If you’ve ever argued internally that “users won’t open suspicious attachments,” the preview pane keeps proving that argument doesn’t fully protect you.

How AI reduces blast radius (even if one machine pops)

For Office-driven exploit chains, AI-driven detection and response can focus on:

• Immediate isolation when Office spawns unusual child processes
• Rapid similarity matching (do other endpoints show the same exploit-like chain?)
• Automated containment (block related indicators, quarantine attachments, restrict risky behaviors temporarily)

This is where AI earns its keep: shortening the interval between first suspicious behavior and coordinated response.

A practical, AI-assisted patch workflow that works in real companies

Most patch programs fail for boring reasons: too many assets, unclear ownership, and not enough time. AI doesn’t fix organizational dysfunction—but it does make good processes faster.

Step 1: Prioritize by “exploit path,” not by CVSS alone

CVSS is useful, but it’s not your patch queue.

For December 2025, a strong priority order looks like:

1. Actively exploited zero-day EoP (CVE-2025-62221) — because exploitation is confirmed
2. Critical Office preview-pane RCEs (CVE-2025-62554, CVE-2025-62557) — because email scale is brutal
3. Publicly disclosed command injection in common tools (Copilot/PowerShell) — because public knowledge compresses timelines

AI-powered exposure management can enhance this by factoring in:

• Whether the vulnerable component is actually installed and used
• Asset criticality (exec laptops, developer workstations, jump boxes)
• Internet exposure and lateral movement potential

Step 2: Use telemetry to find “likely exploited” assets first

If you can’t patch everything immediately, patch what’s most likely to be under pressure.

AI-driven monitoring can flag:

• Endpoints showing unusual privilege escalation attempts
• Sudden spikes in suspicious PowerShell activity
• Office process behavior that deviates from baselines

This approach creates a risk-informed patch ring: you patch the most threatened systems first, not just the most important on paper.

Step 3: Automate the boring parts (and keep humans on decisions)

The right split is:

• AI/automation: asset discovery, patch status validation, correlation, alert deduplication, rollout monitoring
• Humans: exception approval, risk acceptance, business coordination, incident decisions

A good metric here is MTTP (mean time to patch) for the top 5% most dangerous exposures. If you can drive MTTP down, you reduce real-world breach probability.

Step 4: Plan for “no patch yet” scenarios

Not every urgent vulnerability has an easy patch path, and not every patch is safe to deploy instantly. Your playbook should include mitigations you can apply quickly:

• Reduce attack surface (disable risky preview behaviors where feasible)
• Tighten application controls for scripting tools
• Increase monitoring thresholds temporarily for high-risk techniques
• Segment or restrict high-value endpoints (developers, IT admins)

Even when you can patch, mitigations buy you time.

What to do this week (a realistic December checklist)

If you’re reading this in mid-to-late December, you’re probably juggling end-of-year constraints. Here’s what I’d do in the next five business days:

1. Patch CVE-2025-62221 across endpoints and servers where applicable, starting with admin workstations and shared servers.
2. Fast-track Office updates for user endpoints (pilot ring in hours, broad ring in days).
3. Audit developer workstations for JetBrains + Copilot usage and review terminal auto-approve behaviors.
4. Add a PowerShell “high alert mode”: tighten detections for encoded commands, unusual parents, and execution from user-writable paths.
5. Run an exposure report: where are these components installed, and which assets are still unpatched after 72 hours?

Patch Tuesday doesn’t need perfection. It needs speed on the exposures that matter.

Where AI in cybersecurity is headed (and what you should demand)

The direction is clear: security teams are moving from vulnerability management to exposure management, and AI is the only realistic way to keep up with monthly release volume plus real-world exploitation.

When you evaluate tools and programs, demand capabilities that map to outcomes:

• Can it prove whether a vulnerable component is present and active?
• Can it tie vulnerabilities to real attack behavior on endpoints?
• Can it help you prioritize using asset criticality + exploit signals?
• Can it automate containment when exploit-like activity appears?

If the answer is “it gives us a long list,” you don’t have exposure management—you have spreadsheet management.

The forward-looking question worth asking your team is simple: if an exploit chain starts on a single laptop during the holiday lull, how fast can you detect it, contain it, and verify patch coverage across the fleet?