Oracle Linux 7 : Unbreakable Enterprise kernel-container (ELSA-2021-9223)

high Nessus Plugin ID 149420

Synopsis

The remote Oracle Linux host is missing one or more security updates.

Description

The remote Oracle Linux 7 host has a package installed that is affected by multiple vulnerabilities as referenced in the ELSA-2021-9223 advisory.

- An issue was discovered in the Linux kernel before 5.11.8. kernel/bpf/verifier.c performs undesirable out- of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory, aka CID-f232326f6966. This affects pointer types that do not define a ptr_limit. (CVE-2020-27170)

- An issue was discovered in the Linux kernel before 5.11.8. kernel/bpf/verifier.c has an off-by-one error (with a resultant integer underflow) affecting out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory, aka CID-10d2bb2e6b1d. (CVE-2020-27171)

- The fix for XSA-365 includes initialization of pointers such that subsequent cleanup code wouldn't use uninitialized or stale values. This initialization went too far and may under certain conditions also overwrite pointers which are in need of cleaning up. The lack of cleanup would result in leaking persistent grants. The leak in turn would prevent fully cleaning up after a respective guest has died, leaving around zombie domains. All Linux versions having the fix for XSA-365 applied are vulnerable.
XSA-365 was classified to affect versions back to at least 3.11. (CVE-2021-28688)

- A race condition was discovered in get_old_root in fs/btrfs/ctree.c in the Linux kernel through 5.11.8. It allows attackers to cause a denial of service (BUG) because of a lack of locking on an extent buffer before a cloning operation, aka CID-dbcc7d57bffc. (CVE-2021-28964)

- An issue was discovered in the Linux kernel before 5.11.11. The netfilter subsystem allows attackers to cause a denial of service (panic) because net/netfilter/x_tables.c and include/linux/netfilter/x_tables.h lack a full memory barrier upon the assignment of a new table value, aka CID-175e476b8cdf.
(CVE-2021-29650)

- In intel_pmu_drain_pebs_nhm in arch/x86/events/intel/ds.c in the Linux kernel through 5.11.8 on some Haswell CPUs, userspace applications (such as perf-fuzzer) can cause a system crash because the PEBS status in a PEBS record is mishandled, aka CID-d88d05a9e0b6. (CVE-2021-28971)

- BPF JIT compilers in the Linux kernel through 5.11.12 have incorrect computation of branch displacements, allowing them to execute arbitrary code within the kernel context. This affects arch/x86/net/bpf_jit_comp.c and arch/x86/net/bpf_jit_comp32.c. (CVE-2021-29154)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected kernel-uek-container package.

See Also

https://linux.oracle.com/errata/ELSA-2021-9223.html

Plugin Details

Severity: High

ID: 149420

File Name: oraclelinux_ELSA-2021-9223.nasl

Version: 1.3

Type: local

Agent: unix

Published: 5/12/2021

Updated: 9/8/2021

Supported Sensors: Frictionless Assessment Agent, Nessus Agent

Risk Information

CVSS Score Source: CVE-2021-29154

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:oracle:linux:7, p-cpe:/a:oracle:linux:kernel-uek-container

Required KB Items: Host/OracleLinux, Host/RedHat/release, Host/RedHat/rpm-list, Host/local_checks_enabled

Exploit Ease: No known exploits are available

Patch Publication Date: 5/10/2021

Vulnerability Publication Date: 3/20/2021

Reference Information

CVE: CVE-2020-27170, CVE-2020-27171, CVE-2021-3428, CVE-2021-28688, CVE-2021-28964, CVE-2021-28971, CVE-2021-29154, CVE-2021-29650