An issue was discovered in the Linux kernel through 5.10.11. PI futexes have a kernel stack use-after-free during fault handling, allowing local users to execute code in the kernel, aka CID-34b1a1ce1458.

Affected: Ubuntu:18.04:LTS: linux-aws-5.4, Ubuntu:18.04:LTS: linux-azure-5.4, Ubuntu:18.04:LTS: linux-gcp-5.4, Ubuntu:18.04:LTS: linux-gke-5.4, Ubuntu:18.04:LTS: linux-gkeop-5.4, Ubuntu:18.04:LTS: linux-hwe-5.4, Ubuntu:18.04:LTS: linux-oracle-5.4, Ubuntu:18.04:LTS: linux-raspi-5.4, Ubuntu:20.04:LTS: linux, Ubuntu:20.04:LTS: linux-aws and 6 more

It was discovered that the Marvell WiFi-Ex device driver in the Linux kernel did not properly validate ad-hoc SSIDs. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-36158)

Ryota Shiga discovered that the sockopt BPF hooks in the Linux kernel could allow a user space program to probe for valid kernel addresses. A local attacker could use this to ease exploitation of another kernel vulnerability. (CVE-2021-20239)

It was discovered that the priority inheritance futex implementation in the Linux kernel contained a race condition, leading to a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-3347)

吴异 discovered that the NFS implementation in the Linux kernel did not properly prevent access outside of an NFS export that is a subdirectory of a file system. An attacker could possibly use this to bypass NFS access restrictions. (CVE-2021-3178)