SB2021051156 - Ubuntu update for linux
Published: May 11, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 12 secuirty vulnerabilities.
1) Out-of-bounds read (CVE-ID: CVE-2021-3489)
The vulnerability allows a local user to execute arbitrary code.
The vulnerability exists due to an out-of-bounds read error within the __bpf_ringbuf_reserve() function in kernel/bpf/ringbuf.c. A local user can execute arbitrary code.
2) Out-of-bounds write (CVE-ID: CVE-2021-3490)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when processing untrusted input in bpf. The eBPF ALU32 bounds tracking for bitwise ops (AND, OR and XOR) in the
Linux kernel did not properly update 32-bit bounds, which could be
turned into out of bounds reads and writes in the Linux kernel and
therefore, arbitrary code execution. A local user can run a specially crafted program to trigger an out-of-bounds write and execute arbitrary code with elevated privileges.
3) Out-of-bounds write (CVE-ID: CVE-2021-3491)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to the io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS
operation, which led to negative values being used in mem_rw when reading
/proc/<PID>/mem. A local user can trigger a heap overflow and execute arbitrary code with elevated privileges.
4) Null pointer dereference (CVE-ID: CVE-2020-25639)
The vulnerability allows a local privileged user to perform a denial of service (DoS) attack.
A NULL pointer dereference flaw was found in the Linux kernel's GPU Nouveau driver functionality in versions prior to 5.12-rc1 in the way the user calls ioctl DRM_IOCTL_NOUVEAU_CHANNEL_ALLOC. This flaw allows a local user to crash the system.
5) Resource management error (CVE-ID: CVE-2021-26930)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper management of internal resources when processing service requests to the PV backend within drivers/block/xen-blkback/blkback.c driver in Xen. A local user on the guest OS can perform a denial of service (DoS) attack.
6) Allocation of resources without limits or throttling (CVE-ID: CVE-2021-26931)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to allocation of resources without limits or throttling error within the scsiback_gnttab_data_map_batch() function in drivers/xen/xen-scsiback.c. A local user can perform a denial of service (DoS) attack.
7) Missing authorization (CVE-ID: CVE-2021-28375)
The vulnerability allows a local user to execute arbitrary code.
The vulnerability exists due to missing authorization error within the fastrpc_internal_invoke() function in drivers/misc/fastrpc.c. A local user can execute arbitrary code.
8) Input validation error (CVE-ID: CVE-2021-29264)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper input validation within the gfar_add_rx_frag() and gfar_clean_rx_ring() functions in drivers/net/ethernet/freescale/gianfar.c. A local user can perform a denial of service (DoS) attack.
9) Race condition (CVE-ID: CVE-2021-29265)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to a race condition within the usbip_sockfd_store() function in drivers/usb/usbip/stub_dev.c. A local user can perform a denial of service (DoS) attack.
10) Use-after-free (CVE-ID: CVE-2021-29266)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error in drivers/vhost/vdpa.c, because "v->config_ctx" has an invalid value upon re-opening a character device. A local user can trigger a use-after-free error and execute arbitrary code with elevated privileges.
11) Input validation error (CVE-ID: CVE-2021-29646)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper input validation within the tipc_nl_node_dump_monitor_peer() function in net/tipc/node.c. A local user can perform a denial of service (DoS) attack.
12) Buffer overflow (CVE-ID: CVE-2021-29650)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to a boundary error within the netfilter subsystem in net/netfilter/x_tables.c and include/linux/netfilter/x_tables.h. A local user can trigger memory corruption upon the assignment of a new table value and cause denial of service.
Remediation
Install update from vendor's website.