CVE-2024-35825: 
Linux Kernel vulnerability analysis and mitigation

CVE-2024-35825 is a vulnerability in the Linux kernel's USB gadget Network Control Model (NCM) driver, discovered and disclosed in May 2024. The issue affects systems where CDC_NCM_NTB_DEF_SIZE_TX is set to 65536, causing improper handling of zero block length packets (NVD).

The vulnerability occurs when receiving short packets at intervals of 5-10 seconds that have block length zero but still contain 1-2 valid datagrams. The implementation checks for multiple NTBs in a single giveback by verifying if leftover bytes to be processed is zero. When block length reads zero, the same NTB is processed infinitely because leftover bytes never become zero, leading to a system crash (Kernel Commit).

The vulnerability can lead to a denial of service condition through system crash when processing certain USB network communications (Red Hat).

The issue can be triggered when connecting to a Linux host with specific USB network configurations. It requires the CDC_NCM_NTB_DEF_SIZE_TX parameter to be set to 65536 and the processing of zero block length packets (NVD).

The vulnerability has been patched by modifying the USB gadget NCM driver to bail out if block length reads zero. The fix has been incorporated into various Linux kernel versions and distributions including Ubuntu and Debian (Ubuntu Notice, Debian Notice).