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Tag: cwe-416

  • CVE-2025-21307: Critical Remote Code Execution in Windows RMCAST Driver

    Overview

    Microsoft disclosed a critical vulnerability identified as CVE-2025-21307 in the Windows Reliable Multicast Transport (RMCAST) driver on January 14, 2025. This vulnerability allows remote code execution and affects a broad range of Windows versions, including Windows 10, 11, and multiple Windows Server editions. With a CVSS v3.1 base score of 9.8, it is classified as Critical.

    Technical Details

    The root cause of this vulnerability is a Use After Free flaw, classified under CWE-416. This type of issue arises when a program continues to use memory after it has been freed, potentially allowing attackers to execute arbitrary code with kernel-level privileges. RMCAST, as a low-level driver responsible for multicast traffic, becomes a dangerous attack surface when such flaws are present.

    CVSS and Risk Analysis

    According to the CVSS v3.1 vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, this vulnerability is:

    • Remotely exploitable over the network
    • Low complexity to exploit
    • No privileges or user interaction required
    • High impact on confidentiality, integrity, and availability

    The CISA Stakeholder-Specific Vulnerability Categorization (SSVC) assessment noted the potential for automated exploitation and described the technical impact as total.

    Affected Systems

    The vulnerability affects a wide set of Windows versions, including:

    • Windows 10 (1507, 1607, 1809, 21H2, 22H2)
    • Windows 11 (22H2, 23H2, 24H2)
    • Windows Server (2008 SP2, 2008 R2, 2012, 2016, 2019, 2022, 2025)

    Mitigation and Recommendations

    Microsoft has released patches addressing the flaw. To mitigate the risk, administrators should:

    • Apply the latest security updates immediately
    • Implement strict network segmentation and firewall policies
    • Audit multicast usage and disable RMCAST if not required

    Example minimum safe versions include:

    • Windows 10 Version 1809: 10.0.17763.6775 or later
    • Windows Server 2022: 10.0.20348.3091 or later
    • Windows 11 22H2: 10.0.22621.4751 or later

    Conclusion

    CVE-2025-21307 presents a critical risk due to its remote exploitability, lack of prerequisites, and broad impact across Windows ecosystems. Timely patching and proactive mitigation strategies are essential to secure systems against this vulnerability.

    Read the full advisory on the Microsoft Security Update Guide.

  • CVE-2025-21307: Critical Remote Code Execution in Windows RMCAST Driver

    Overview

    On January 14, 2025, Microsoft disclosed CVE-2025-21307, a critical vulnerability in the Windows Reliable Multicast Transport (RMCAST) driver that enables remote code execution. With a CVSS v3.1 base score of 9.8, this vulnerability poses a severe threat to numerous supported and legacy Windows systems.

    Technical Details

    The issue stems from a Use After Free vulnerability, classified as CWE-416. This occurs when a program continues to use a pointer after it has been freed, allowing an attacker to exploit the dangling pointer to execute arbitrary code within the kernel space. Given that RMCAST operates at a low-level networking layer, this provides an attacker significant control over system behavior once exploited.

    The vulnerability affects a wide range of Windows versions, including:

    • Windows 10 (versions 1507, 1607, 1809, 21H2, 22H2)
    • Windows 11 (versions 22H2, 23H2, 24H2)
    • Windows Server (2008 SP2, 2008 R2 SP1, 2012, 2012 R2, 2016, 2019, 2022, 2025)

    Exploitation does not require authentication or user interaction, and the attack can be carried out over the network, making it highly dangerous in unsegmented or exposed environments.

    Impact

    According to the CVSS v3.1 vector (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), this vulnerability allows:

    • Confidentiality Impact: High
    • Integrity Impact: High
    • Availability Impact: High

    The vulnerability is not known to be exploited in the wild at the time of disclosure, and Microsoft has issued updates to remediate the issue. The CISA SSVC analysis classified this flaw as having a total technical impact with the potential for automated exploitation, emphasizing the urgency for mitigation.

    Mitigation and Recommendations

    Microsoft has released patches through its regular update channels. All affected systems should be updated immediately to versions beyond:

    • 10.0.17763.6775 (Windows 10 Version 1809)
    • 10.0.20348.3091 (Windows Server 2022)
    • 10.0.22621.4751 (Windows 11 22H2)

    System administrators are encouraged to:

    • Deploy patches as soon as possible.
    • Use network segmentation and firewalls to reduce the attack surface.
    • Audit multicast traffic and disable RMCAST if not in use.

    Conclusion

    CVE-2025-21307 represents a serious risk due to its low complexity, remote exploitability, and severe impact. With broad applicability across many supported and end-of-life systems, proactive patching is essential. Organizations should prioritize this vulnerability and monitor vendor advisories for ongoing updates.

    For further information, visit the official Microsoft advisory.

  • Critical Windows OLE Remote Code Execution Vulnerability (CVE-2025-21298)

    Overview

    CVE-2025-21298 is a critical vulnerability in Microsoft Windows related to the Object Linking and Embedding (OLE) technology. The flaw enables remote code execution (RCE) through a ‘use-after-free’ condition, classified under CWE-416. This vulnerability impacts a wide range of Windows operating systems and server editions, making it one of the most severe security issues addressed in early 2025.

    Technical Details

    The root cause of this vulnerability lies in improper memory management during the handling of OLE objects. An attacker can exploit a use-after-free error to execute arbitrary code in the context of the user running the affected application. The attack vector is remote and does not require prior authentication or user interaction.

    The vulnerability is identified by the following CVSS v3.1 vector:

    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

    • Base Score: 9.8 (Critical)
    • Attack Vector: Network
    • Attack Complexity: Low
    • Privileges Required: None
    • User Interaction: None
    • Impact: High on confidentiality, integrity, and availability

    Affected Systems

    This vulnerability affects a broad set of Windows versions, including:

    • Windows 10 (various builds from 1507 to 22H2)
    • Windows 11 (22H2, 23H2, 24H2)
    • Windows Server (2008 SP2, 2012, 2016, 2019, 2022, 2025)

    Mitigation and Recommendations

    • Apply security updates released in the January 2025 Patch Tuesday immediately.
    • Restrict OLE functionality where not needed, especially in environments handling untrusted content.
    • Monitor systems for signs of exploitation, particularly for abnormal memory access patterns or unexpected OLE behaviors.

    Conclusion

    CVE-2025-21298 demonstrates the persistent threat of memory safety vulnerabilities in complex, legacy components like OLE. Organizations must apply updates promptly and evaluate mitigation controls for high-risk environments.

    For more details, see the official Microsoft advisory: MSRC: CVE-2025-21298