CVE-2026-45476 – Microsoft Azure Network Adapter Elevation of Privilege Vulnerability

CVE-2026-45476 is a Critical elevation of privilege vulnerability affecting the Microsoft Azure Network Adapter through the Linux MANA Driver. The vulnerability is caused by a use-after-free condition that could allow an attacker with existing control of the host environment to gain elevated privileges within a guest system. Successful exploitation may enable access to resources beyond the original security boundary, increasing the overall impact of an attack.

CVSS Score: 8.2
SEVERITY: Critical
THREAT:
This vulnerability presents a risk to environments using the Microsoft Azure Network Adapter and Linux MANA Driver. An attacker who already has significant access to the host environment could exploit a memory handling flaw in the guest driver. The vulnerability is particularly notable because exploitation can result in a scope change, allowing impact beyond the original security context.

EXPLOITS:
Publicly Disclosed: No.
Exploited: No.
Exploitability Assessment: Exploitation Less Likely.
No public exploit, zero-day exploitation, or proof-of-concept code is confirmed in the provided data.

TECHNICAL SUMMARY:
CVE-2026-45476 is caused by a use-after-free vulnerability, identified as CWE-416, in the Linux MANA Driver used by the Microsoft Azure Network Adapter. Use-after-free vulnerabilities occur when software continues to access memory after it has been released, potentially allowing unintended memory manipulation or disclosure. According to the provided information, an attacker who already controls the host environment could trigger memory handling flaws within the guest driver. This may allow access to sensitive information and enable further privilege escalation. The CVSS v3.1 metrics show local attack vector, low attack complexity, high privileges required, no user interaction, changed scope, and high impact to confidentiality, integrity, and availability.

EXPLOITABILITY:
Affected software:
Linux kernel – Microsoft MANA Network Driver
Exploitation requires high privileges and control of the host environment. No user interaction is required. Successful exploitation could allow an attacker to gain elevated privileges within the guest system.

BUSINESS IMPACT:
This vulnerability is particularly important in cloud and virtualized environments where strong isolation between host and guest systems is critical. A successful attack could expose sensitive guest data, weaken trust boundaries, and increase the impact of an existing compromise. Organizations relying on Azure-hosted Linux workloads may face risks to confidentiality, operational integrity, and system trust if vulnerable systems remain unpatched.

WORKAROUND:
No mitigations or workarounds are listed.
Where immediate patching is not possible, restrict privileged access to host environments, monitor virtualization infrastructure for unusual activity, and review access controls for systems managing guest workloads.

URGENCY:
This patch should be prioritized because the vulnerability is rated Critical and involves a scope change, meaning the impact can extend beyond the vulnerable component itself. While exploitation requires high privileges and is assessed as less likely, successful exploitation could weaken isolation boundaries and lead to elevated access within guest environments.