CVE-2024-56772

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to 6.12.0-rc4+

Description A Use-After-Free (UAF) bug has been fixed in the Linux kernel's KUnit string stream function. The issue occurs when alloc string stream() fails in the kunit suite for each test case() loop, causing the suite->log stream memory to be freed but not set to NULL. This leads to a UAF bug when string stream clear() is called later. The error path only frees the suite->log stream memory but not sets it to NULL, resulting in a UAF bug.

Technical details about exploitation include:

Recommendations To resolve the issue, update the Linux kernel to a version that includes the fix for the UAF bug. As a temporary workaround, consider disabling the string stream clear() function until a patch is available. Restrict access to the vulnerable kunit debugfs create suite() function to minimize the risk of exploitation. Avoid using the suite->log stream in the affected API endpoint until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this vulnerability.