CVE-2024-27028: 
Linux Kernel vulnerability analysis and mitigation

CVE-2024-27028 is a vulnerability discovered in the Linux kernel's MediaTek SPI (spi-mt65xx) driver. The issue was identified and disclosed on May 1, 2024, affecting the interrupt handler functionality where the TX buffer in spi_transfer could be a NULL pointer, potentially leading to invalid memory access and system crashes (NVD).

The vulnerability exists in the interrupt handler of the MediaTek SPI driver where the code attempts to access the tx_buf pointer without proper NULL pointer validation. The issue stems from a bug introduced in commit 1ce24864bff4 ("spi: mediatek: Only do dma for 4-byte aligned buffers"). The CVSS v3.1 base score is 6.5 (Medium), with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L (NVD).

When exploited, this vulnerability can cause system crashes due to invalid memory access when the interrupt handler attempts to write to memory using an unvalidated NULL pointer (NVD).

The vulnerability requires local access to the system and can be triggered through the SPI interface when the tx_buf pointer is NULL. No known exploits in the wild have been reported (NVD).

The issue has been fixed by adding a check for trans->tx_buf before using it in the interrupt handler. The fix has been incorporated into various Linux kernel versions, including Ubuntu 24.04 LTS (6.8.0-35.35), 22.04 LTS (5.15.0-112.122), and 20.04 LTS (5.4.0-189.209) (Ubuntu).