SB2021073014 - SUSE update for the Linux Kernel (Live Patch 15 for SLE 15 SP2)
Published: July 30, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 15 secuirty vulnerabilities.
1) Improper Resource Shutdown or Release (CVE-ID: CVE-2020-36322)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists in the FUSE filesystem implementation in the Linux kernel due to fuse_do_getattr() calls make_bad_inode() in inappropriate situations. A local user can run a specially crafted program to trigger kernel crash.
Note, the vulnerability exists due to incomplete fix for #VU58207 (CVE-2021-28950).
2) Use-after-free (CVE-ID: CVE-2020-36385)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error in drivers/infiniband/core/ucma.c, because the ctx is reached via the ctx_list in some ucma_migrate_id situations where ucma_close is called. A local user can run a specially crafted program to trigger the use-after-free error and execute arbitrary code with elevated privileges.
3) Out-of-bounds write (CVE-ID: CVE-2021-22555)
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 net/netfilter/x_tables.c in Linux kernel. A local user can run a specially crafted program to trigger an out-of-bounds write and execute arbitrary code with elevated privileges.
4) Race condition (CVE-ID: CVE-2021-23133)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a race condition in Linux kernel SCTP sockets (net/sctp/socket.c). If sctp_destroy_sock is called without
sock_net(sk)->sctp.addr_wq_lock then an element is removed from the
auto_asconf_splist list without any proper locking. This can be
exploited by a local user with network service privileges to escalate to
root or from the context of an unprivileged user directly if a
BPF_CGROUP_INET_SOCK_CREATE is attached which denies creation of some
SCTP socket.
5) Information disclosure (CVE-ID: CVE-2021-27363)
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to the show_transport_handle() shows iSCSI transport handle to non-root users. A local user can gain unauthorized access to sensitive information and use it along with another vulnerability, such as #VU51452, to escalate privileges on the system.
6) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2021-27364)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to iscsi_if_recv_msg() allows non-root users to connect and send commands to the Linux kernel. A local user can escalate privileges on the system.
7) Buffer overflow (CVE-ID: CVE-2021-27365)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when processing Netlink messages in Linux kernel through 5.11.3, as certain iSCSI data structures do not have appropriate length constraints or checks, and can exceed the PAGE_SIZE value. A local unprivileged user can send a Netlink message that is associated with iSCSI, and has a length up to the maximum length of a Netlink message, trigger memory corruption and execute arbitrary code on the system with elevated privileges.
8) Out-of-bounds write (CVE-ID: CVE-2021-28660)
The vulnerability allows a local user to compromise vulnerable system.
The vulnerability exists due to a boundary error when processing untrusted input in the "rtw_wx_set_scan" in drivers/staging/rtl8188eu/os_dep/ioctl_linux.c. A local user can trigger out-of-bounds write and execute arbitrary code on the target system.
9) Improper Initialization (CVE-ID: CVE-2021-28688)
The vulnerability allows a local user to perform a denial of service attack.
The vulnerability exists due to improper initialization of pointers such that subsequent cleanup code wouldn't use uninitialized or stale values. A local user can perform a denial of service attack.
10) Command Injection (CVE-ID: CVE-2021-29154)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to incorrect computation of branch displacements within the BPF JIT compilers in the Linux kernel in arch/x86/net/bpf_jit_comp.c and arch/x86/net/bpf_jit_comp32.c. A local user can inject and execute arbitrary commands with elevated privileges.
11) Race condition (CVE-ID: CVE-2021-32399)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a race condition for removal of the HCI controller within net/bluetooth/hci_request.c in the Linux kernel. A local user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.
12) Use-after-free (CVE-ID: CVE-2021-33034)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error in net/bluetooth/hci_event.c when destroying an hci_chan. A local user can escalate privileges on the system.
13) Integer overflow (CVE-ID: CVE-2021-33909)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to integer overflow during size_t-to-int conversion when creating, mounting, and deleting a deep directory structure whose total path length exceeds 1GB. An unprivileged local user can write up to 10-byte string to an offset of exactly -2GB-10B below the beginning of a vmalloc()ated kernel buffer.
Successful exploitation of vulnerability may allow an attacker to exploit the our-of-bounds write vulnerability to execute arbitrary code with root privileges.
14) Out-of-bounds read (CVE-ID: CVE-2021-3444)
The vulnerability allows a local user to execute arbitrary code.
The vulnerability exists due to an out-of-bounds read error within the fixup_bpf_calls() function in kernel/bpf/verifier.c. A local user can execute arbitrary code.
15) Excessive Iteration (CVE-ID: CVE-2021-28950)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to excessive iteration in fs/fuse/fuse_i.h in the Linux kernel. A local user can run a specially crafted program to perform a denial of service attack.
Remediation
Install update from vendor's website.