SB2021062916 - SUSE update for the Linux Kernel (Live Patch 0 for SLE 15 SP3)

Description

This security bulletin contains information about 7 vulnerabilities.

1) Improper Resource Shutdown or Release (CVE-ID: CVE-2020-36322)

CWE-ID: CWE-404 - Improper Resource Shutdown or Release

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

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) Out-of-bounds write (CVE-ID: CVE-2021-28660)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

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.

3) Command Injection (CVE-ID: CVE-2021-29154)

CWE-ID: CWE-77 - Command injection

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

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.

4) Race condition (CVE-ID: CVE-2021-32399)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

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.

5) Use-after-free (CVE-ID: CVE-2021-33034)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

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.

6) Out-of-bounds read (CVE-ID: CVE-2021-3489)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

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.

7) Out-of-bounds write (CVE-ID: CVE-2021-3490)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Clear

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.

Remediation

Install update from vendor's website.

References

• https://www.suse.com/support/update/announcement/2021/suse-su-20212198-1/