Ubuntu 20.04 LTS : Linux kernel (Azure CVM) vulnerabilities (USN-5706-1)


The remote Ubuntu 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-5706-1 advisory. - A vulnerability was found in the Linux kernel's EBPF verifier when handling internal data structures. Internal memory locations could be returned to userspace. A local attacker with the permissions to insert eBPF code to the kernel can use this to leak internal kernel memory details defeating some of the exploit mitigations in place for the kernel. (CVE-2021-4159) - There are use-after-free vulnerabilities caused by timer handler in net/rose/rose_timer.c of linux that allow attackers to crash linux kernel without any privileges. (CVE-2022-2318) - There exists a use-after-free in io_uring in the Linux kernel. Signalfd_poll() and binder_poll() use a waitqueue whose lifetime is the current task. It will send a POLLFREE notification to all waiters before the queue is freed. Unfortunately, the io_uring poll doesn't handle POLLFREE. This allows a use-after-free to occur if a signalfd or binder fd is polled with io_uring poll, and the waitqueue gets freed. We recommend upgrading past commit fc78b2fc21f10c4c9c4d5d659a685710ffa63659 (CVE-2022-3176) - In v4l2_m2m_querybuf of v4l2-mem2mem.c, there is a possible out of bounds write due to improper input validation. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-223375145References: Upstream kernel (CVE-2022-20369) - Linux disk/nic frontends data leaks T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Linux Block and Network PV device frontends don't zero memory regions before sharing them with the backend (CVE-2022-26365, CVE-2022-33740). Additionally the granularity of the grant table doesn't allow sharing less than a 4K page, leading to unrelated data residing in the same 4K page as data shared with a backend being accessible by such backend (CVE-2022-33741, CVE-2022-33742). (CVE-2022-26365, CVE-2022-33740, CVE-2022-33741, CVE-2022-33742) - Non-transparent sharing of return predictor targets between contexts in some Intel(R) Processors may allow an authorized user to potentially enable information disclosure via local access. (CVE-2022-26373) - Arm guests can cause Dom0 DoS via PV devices When mapping pages of guests on Arm, dom0 is using an rbtree to keep track of the foreign mappings. Updating of that rbtree is not always done completely with the related lock held, resulting in a small race window, which can be used by unprivileged guests via PV devices to cause inconsistencies of the rbtree. These inconsistencies can lead to Denial of Service (DoS) of dom0, e.g. by causing crashes or the inability to perform further mappings of other guests' memory pages. (CVE-2022-33744) - An issue was discovered in the Linux kernel through 5.18.14. xfrm_expand_policies in net/xfrm/xfrm_policy.c can cause a refcount to be dropped twice. (CVE-2022-36879) Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.