Full Report
Microsoft on Tuesday released security updates to address a set of 59 flaws across its software, including six vulnerabilities that it said have been exploited in the wild. Of the 59 flaws, five are rated Critical, 52 are rated Important, and two are rated Moderate in severity. Twenty-five of the patched vulnerabilities have been classified as privilege escalation, followed by remote code
Analysis Summary
The provided context summarizes Microsoft's February 2026 Patch Tuesday release, which addresses 59 vulnerabilities, including six actively exploited zero-day flaws. Since specific patch numbers and detailed product lists for all 59 flaws are not enumerated individually in the text, the summary below focuses intensely on the six **actively exploited** vulnerabilities detailed. Other general statistics about the release are noted where possible.
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# Vulnerability: Actively Exploited Zero-Day Flaws in Microsoft Products (Feb 2026)
## CVE Details
This summary focuses on the six actively exploited vulnerabilities mentioned:
| CVE ID | CVSS Score | Severity Note | Primary Flaw Type (Implied) |
| :--- | :--- | :--- | :--- |
| **CVE-2026-21510** | 8.8 (High) | Important (Implied from other 8.8s) | Protection Mechanism Failure / Security Feature Bypass |
| **CVE-2026-21513** | 8.8 (High) | Important (Implied from other 8.8s) | Protection Mechanism Failure / Security Feature Bypass |
| **CVE-2026-21514** | 7.8 (High) | Important (Implied from other 7.8s) | Reliance on Untrusted Inputs / Security Feature Bypass |
| **CVE-2026-21519** | 7.8 (High) | Important (Implied from other 7.8s) | Type Confusion / Privilege Escalation |
| **CVE-2026-21525** | 6.2 (Medium) | Important (Implied from other scores) | Null Pointer Dereference / Denial of Service |
| **CVE-2026-21533** | 7.8 (High) | Important (Implied from other 7.8s) | Improper Privilege Management / Privilege Escalation |
*Note: Overall severity distribution for all 59 flaws: 5 Critical, 52 Important, 2 Moderate. CWE details are not provided, but flaw types are inferred from descriptions.*
## Affected Systems
- **Products:** Windows Shell, MSHTML Framework, Microsoft Office Word, Desktop Window Manager, Windows Remote Access Connection Manager, Windows Remote Desktop. (Specific product/build versions are not listed in the text snippet).
- **Versions:** Unknown (Official Microsoft security updates are required for specific version guidance).
- **Configurations:** Exploitation context varies based on the specific CVE: Network (CVE-21510, CVE-21513), Local (CVE-21514, CVE-21519, CVE-21525, CVE-21533).
## Vulnerability Description
The 59 flaws addressed include 25 privilege escalation flaws and 12 remote code execution flaws. The six actively exploited vulnerabilities feature:
1. **CVE-2026-21510 & CVE-2026-21513:** Protection mechanism failures leading to security feature bypasses. CVE-2026-21513 specifically affects the MSHTML Framework, allowing bypass of execution prompts upon interaction with malicious files (potentially HTML/Office files).
2. **CVE-2026-21514:** Reliance on untrusted inputs in Microsoft Office Word leading to a local security feature bypass.
3. **CVE-2026-21519:** A type confusion vulnerability in the Desktop Window Manager leading to local privilege escalation.
4. **CVE-2026-21525:** A null pointer dereference in Windows Remote Access Connection Manager leading to a local Denial of Service (DoS).
5. **CVE-2026-21533:** Improper privilege management in Windows Remote Desktop allowing local privilege escalation.
## Exploitation
- **Status:** **Exploited in the wild** (Identified for all six listed CVEs). The first three (CVE-2026-21510, CVE-2026-21513, CVE-2026-21514) were also reported as publicly known at the time of release.
- **Complexity:** Varies (Network exploits generally imply lower complexity than local ones, but specific details are absent).
- **Attack Vector:** Varies (Network, Local).
*Detailed exploitation mechanisms are currently undisclosed ("no details on how the vulnerabilities are being exploited").*
## Impact
Impact severity is inferred from known exploit types:
- **Confidentiality:** Potential loss for RCE and Privilege Escalation flaws.
- **Integrity:** Potential compromise via Privilege Escalation and Security Feature Bypass flaws.
- **Availability:** Potential loss due to the Denial of Service vulnerability (CVE-2026-21525).
## Remediation
### Patches
- Direct patch links or version numbers are not provided in the summary, but Microsoft released updates addressing all 59 flaws. Users must consult the **February 2026 Security Update Guide**.
- Edge browser patches were released separately, noting the fix for **CVE-2026-0391** (Moderate, CVSS 6.5, Spoofing on Edge for Android).
### Workarounds
- No specific workarounds are listed for the six zero-day vulnerabilities in this summary. Immediate patching is the priority, especially given active exploitation.
## Detection
- **Indicators of Compromise:** Not detailed in the source text.
- **Detection methods and tools:** Organizations should prioritize endpoint detection and response (EDR) systems capable of monitoring process activity related to unexpected execution prompts or memory access anomalies associated with Windows components (Shell, DWM, RDP). Given the exploitation context, monitoring for suspicious file interaction (Office/HTML files) initiating unexpected processes is critical.
## References
- Vendor Advisories: [MSRC Update Guide (General Reference)](https://msrc.microsoft.com/update-guide/releaseNote/2026-feb)
- Relevant Links:
- Security Update Release Notes: [https://msrc.microsoft.com/update-guide/releaseNote/2026-feb](https://msrc.microsoft.com/update-guide/releaseNote/2026-feb)
- Microsoft Edge Flaw Reference: [https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-0391](https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-0391)
- Vendor/Researcher Commentary on CVE-2026-21513: [https://www.action1.com/patch-tuesday/patch-tuesday-february-2026/](https://www.action1.com/patch-tuesday/patch-tuesday-february-2026/)