An internal reference count is held on the buffer pool, incremented every time a new buffer is created from the pool. The reference count is maintained as an int; on LP64 systems this can cause the reference count to overflow if the client creates a large number of wl_shm buffer objects, or if it can coerce the server to create a large number of external references to the buffer storage. With the reference count overflowing, a use-after-free can be constructed on the wl_shm_pool tracking structure, where values may be incremented or decremented; it may also be possible to construct a limited oracle to leak 4 bytes of server-side memory to the attacking client at a time.
Published: 2022-09-23Modified: 2025-05-22
CVSS 3.xMEDIUM 6.6
CVSS:3.x/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H