ALINUX2-SA-2020%3A0113

Package updates are available for Alibaba Cloud Linux 2.1903 that fix the following vulnerabilities: CVE-2020-10732: A flaw was found in the Linux kernel's implementation of Userspace core dumps. This flaw allows an attacker with a local account to crash a trivial program and exfiltrate private kernel data. CVE-2020-12768: ** DISPUTED ** An issue was discovered in the Linux kernel before 5.6. svm_cpu_uninit in arch/x86/kvm/svm.c has a memory leak, aka CID-d80b64ff297e. NOTE: third parties dispute this issue because it's a one-time leak at the boot, the size is negligible, and it can't be triggered at will. CVE-2020-10711: A NULL pointer dereference flaw was found in the Linux kernel's SELinux subsystem in versions before 5.7. This flaw occurs while importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into the SELinux extensible bitmap via the' ebitmap_netlbl_import' routine. While processing the CIPSO restricted bitmap tag in the 'cipso_v4_parsetag_rbm' routine, it sets the security attribute to indicate that the category bitmap is present, even if it has not been allocated. This issue leads to a NULL pointer dereference issue while importing the same category bitmap into SELinux. This flaw allows a remote network user to crash the system kernel, resulting in a denial of service. CVE-2020-10751: A flaw was found in the Linux kernels SELinux LSM hook implementation before version 5.7, where it incorrectly assumed that an skb would only contain a single netlink message. The hook would incorrectly only validate the first netlink message in the skb and allow or deny the rest of the messages within the skb with the granted permission without further processing. CVE-2020-12114: A pivot_root race condition in fs/namespace.c in the Linux kernel 4.4.x before 4.4.221, 4.9.x before 4.9.221, 4.14.x before 4.14.178, 4.19.x before 4.19.119, and 5.x before 5.3 allows local users to cause a denial of service (panic) by corrupting a mountpoint reference counter. CVE-2019-19768: In the Linux kernel 5.4.0-rc2, there is a use-after-free (read) in the __blk_add_trace function in kernel/trace/blktrace.c (which is used to fill out a blk_io_trace structure and place it in a per-cpu sub-buffer). CVE-2020-1749: A flaw was found in the Linux kernel's implementation of some networking protocols in IPsec, such as VXLAN and GENEVE tunnels over IPv6. When an encrypted tunnel is created between two hosts, the kernel isn't correctly routing tunneled data over the encrypted link; rather sending the data unencrypted. This would allow anyone in between the two endpoints to read the traffic unencrypted. The main threat from this vulnerability is to data confidentiality. CVE-2020-10942: In the Linux kernel before 5.5.8, get_raw_socket in drivers/vhost/net.c lacks validation of an sk_family field, which might allow attackers to trigger kernel stack corruption via crafted system calls. CVE-2020-11565: ** DISPUTED ** An issue was discovered in the Linux kernel through 5.6.2. mpol_parse_str in mm/mempolicy.c has a stack-based out-of-bounds write because an empty nodelist is mishandled during mount option parsing, aka CID-aa9f7d5172fa. NOTE: Someone in the security community disagrees that this is a vulnerability because the issue “is a bug in parsing mount options which can only be specified by a privileged user, so triggering the bug does not grant any powers not already held.”. CVE-2019-19241: In the Linux kernel before 5.4.2, the io_uring feature leads to requests that inadvertently have UID 0 and full capabilities, aka CID-181e448d8709. This is related to fs/io-wq.c, fs/io_uring.c, and net/socket.c. For example, an attacker can bypass intended restrictions on adding an IPv4 address to the loopback interface. This occurs because IORING_OP_SENDMSG operations, although requested in the context of an unprivileged user, are sometimes performed by a kernel worker thread without considering that context. CVE-2019-20096: In the Linux kernel before 5.1, there is a memory leak in __feat_register_sp() in net/dccp/feat.c, which may cause denial of service, aka CID-1d3ff0950e2b. CVE-2019-19965: In the Linux kernel through 5.4.6, there is a NULL pointer dereference in drivers/scsi/libsas/sas_discover.c because of mishandling of port disconnection during discovery, related to a PHY down race condition, aka CID-f70267f379b5. CVE-2019-14615: Insufficient control flow in certain data structures for some Intel(R) Processors with Intel(R) Processor Graphics may allow an unauthenticated user to potentially enable information disclosure via local access. CVE-2019-19077: A memory leak in the bnxt_re_create_srq() function in drivers/infiniband/hw/bnxt_re/ib_verbs.c in the Linux kernel through 5.3.11 allows attackers to cause a denial of service (memory consumption) by triggering copy to udata failures, aka CID-4a9d46a9fe14. CVE-2019-19046: ** DISPUTED ** A memory leak in the __ipmi_bmc_register() function in drivers/char/ipmi/ipmi_msghandler.c in the Linux kernel through 5.3.11 allows attackers to cause a denial of service (memory consumption) by triggering ida_simple_get() failure, aka CID-4aa7afb0ee20. NOTE: third parties dispute the relevance of this because an attacker cannot realistically control this failure at probe time. CVE-2020-8648: There is a use-after-free vulnerability in the Linux kernel through 5.5.2 in the n_tty_receive_buf_common function in drivers/tty/n_tty.c. CVE-2020-8647: There is a use-after-free vulnerability in the Linux kernel through 5.5.2 in the vc_do_resize function in drivers/tty/vt/vt.c. CVE-2020-8649: There is a use-after-free vulnerability in the Linux kernel through 5.5.2 in the vgacon_invert_region function in drivers/video/console/vgacon.c. CVE-2020-8428: fs/namei.c in the Linux kernel before 5.5 has a may_create_in_sticky use-after-free, which allows local users to cause a denial of service (OOPS) or possibly obtain sensitive information from kernel memory, aka CID-d0cb50185ae9. One attack vector may be an open system call for a UNIX domain socket, if the socket is being moved to a new parent directory and its old parent directory is being removed. CVE-2019-3016: In a Linux KVM guest that has PV TLB enabled, a process in the guest kernel may be able to read memory locations from another process in the same guest. This problem is limit to the host running linux kernel 4.10 with a guest running linux kernel 4.16 or later. The problem mainly affects AMD processors but Intel CPUs cannot be ruled out. CVE-2020-2732: A flaw was discovered in the way that the KVM hypervisor handled instruction emulation for an L2 guest when nested virtualisation is enabled. Under some circumstances, an L2 guest may trick the L0 guest into accessing sensitive L1 resources that should be inaccessible to the L2 guest.