CVE-2024-44950

A flaw was found in the Linux kernel's sc16is7xx serial driver. A race condition occurs when the driver accesses special register sets without proper locking while interrupt handling is active. This can cause the interrupt handler to read from an incorrectly mapped register instead of the intended First-In, First-Out (FIFO) buffer. A local user could exploit this flaw to cause data corruption or a Denial of Service (DoS).

A MODERATE severity race condition flaw was found in the Linux kernel sc16is7xx serial driver. When the driver enables access to the device's special register set to program the baud rate divisor (DLL/DLH) registers, a receiver time-out or RHR interrupt can fire during this window. The interrupt handler then reads the receive FIFO through the RHR register at address 0x00, which is remapped to the DLL register while the special register set is enabled, resulting in an erroneous FIFO read. A local user able to trigger this race could cause data corruption or a denial of service on the affected serial port. Red Hat Enterprise Linux 6, 7, 8, and 9 (kernel and kernel-rt) are not affected by this flaw; the affected Red Hat product scope is limited to Fedora, where the fix is delegated to the community kernel maintainers. Red Hat rates this flaw MODERATE with a CVSS 3.1 score of 5.6 (AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:H). This differs from the CVE.org score of 7.1 because Red Hat's scoring reflects that exploitation requires highly privileged local access, whereas the CVE.org vector assumes low privileges.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.