CVE-2026-72065 in Linux
Summary
by MITRE • 08/15/2026
In the Linux kernel, the following vulnerability has been resolved:
net: mana: Validate the packet length reported by the NIC
Validate the packet length reported in the RX CQE before passing it to skb processing. The CQE is supplied by the NIC device and should not be blindly trusted.
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Analysis
by VulDB Data Team • 08/23/2026
The vulnerability identified in the Linux kernel's net/mana subsystem represents a critical validation flaw that could enable malicious packet processing through untrusted network interface card reports. This issue specifically affects the Microsoft Azure Network Adapter (MANA) driver implementation where the kernel fails to properly validate packet length information provided by the hardware device. The flaw stems from the driver's reliance on data directly supplied by the Network Interface Controller without adequate verification of its integrity or legitimacy.
The technical implementation of this vulnerability occurs within the Receive Completion Queue Entry (CQE) processing logic where the kernel receives packet metadata from the hardware device. The CQE contains critical information including packet length that is used to construct network sk_buff structures for further processing. When the kernel does not validate these reported lengths, it creates an opportunity for attackers to manipulate the packet size values in ways that could lead to memory corruption or unexpected behavior during packet handling operations.
This vulnerability operates at the intersection of hardware abstraction layer security and kernel network processing reliability. The flaw allows for potential buffer overflow conditions when malformed packet length values are passed to the standard socket buffer processing functions. According to CWE classification, this represents a weakness in validation of externally-provided data, specifically CWE-20, which covers "Improper Input Validation." The issue also aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter: Python, though more directly related to system-level exploitation techniques that leverage kernel vulnerabilities.
The operational impact of this vulnerability extends beyond simple data corruption scenarios as it creates potential pathways for privilege escalation or denial of service conditions. When the kernel processes packets with invalid length values, it may attempt to allocate memory structures that exceed available bounds or access memory locations outside expected parameters. This can result in system crashes, memory corruption, or potentially allow attackers to execute arbitrary code within kernel space if proper bounds checking is not enforced.
Mitigation strategies for this vulnerability require implementing strict validation of all packet length indicators received from hardware devices before they are processed by kernel network subsystems. The fix involves adding comprehensive checks that verify the reported packet lengths against expected ranges and maximum allowable values. This approach aligns with defensive programming principles and follows industry best practices for hardware abstraction layer security. System administrators should ensure that affected kernels are updated to versions containing the validation patches, while also implementing monitoring solutions that can detect anomalous packet length patterns that might indicate exploitation attempts.
The vulnerability demonstrates the critical importance of never trusting hardware-reported data without proper validation, particularly in kernel-level network processing where a single malformed value could compromise entire system operations. This flaw serves as a reminder of the essential security measures required when implementing hardware abstraction layers and the necessity of maintaining robust input validation throughout all system components that interface with external devices.