Synopsis
The remote Amazon Linux 2 host is missing a security update.
Description
The version of kernel installed on the remote host is prior to 5.4.231-137.341. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2KERNEL-5.4-2023-042 advisory.
- A flaw was found in the Linux kernel's Layer 2 Tunneling Protocol (L2TP). A missing lock when clearing sk_user_data can lead to a race condition and NULL pointer dereference. A local user could use this flaw to potentially crash the system causing a denial of service. (CVE-2022-4129)
- In the Linux kernel before 6.1.6, a NULL pointer dereference bug in the traffic control subsystem allows an unprivileged user to trigger a denial of service (system crash) via a crafted traffic control configuration that is set up with tc qdisc and tc class commands. This affects qdisc_graft in net/sched/sch_api.c. (CVE-2022-47929)
- The current implementation of the prctl syscall does not issue an IBPB immediately during the syscall. The ib_prctl_set function updates the Thread Information Flags (TIFs) for the task and updates the SPEC_CTRL MSR on the function __speculation_ctrl_update, but the IBPB is only issued on the next schedule, when the TIF bits are checked. This leaves the victim vulnerable to values already injected on the BTB, prior to the prctl syscall. The patch that added the support for the conditional mitigation via prctl (ib_prctl_set) dates back to the kernel 4.9.176. We recommend upgrading past commit a664ec9158eeddd75121d39c9a0758016097fa96 (CVE-2023-0045)
- A NULL pointer dereference flaw was found in rawv6_push_pending_frames in net/ipv6/raw.c in the network subcomponent in the Linux kernel. This flaw causes the system to crash. (CVE-2023-0394)
- Copy_from_user on 64-bit versions of the Linux kernel does not implement the __uaccess_begin_nospec allowing a user to bypass the access_ok check and pass a kernel pointer to copy_from_user(). This would allow an attacker to leak information. We recommend upgrading beyond commit 74e19ef0ff8061ef55957c3abd71614ef0f42f47 (CVE-2023-0459)
- There is a use-after-free vulnerability in the Linux Kernel which can be exploited to achieve local privilege escalation. To reach the vulnerability kernel configuration flag CONFIG_TLS or CONFIG_XFRM_ESPINTCP has to be configured, but the operation does not require any privilege. There is a use-after-free bug of icsk_ulp_data of a struct inet_connection_sock. When CONFIG_TLS is enabled, user can install a tls context (struct tls_context) on a connected tcp socket. The context is not cleared if this socket is disconnected and reused as a listener. If a new socket is created from the listener, the context is inherited and vulnerable. The setsockopt TCP_ULP operation does not require any privilege. We recommend upgrading past commit 2c02d41d71f90a5168391b6a5f2954112ba2307c (CVE-2023-0461)
- A memory corruption flaw was found in the Linux kernel's human interface device (HID) subsystem in how a user inserts a malicious USB device. This flaw allows a local user to crash or potentially escalate their privileges on the system. (CVE-2023-1073)
- cbq_classify in net/sched/sch_cbq.c in the Linux kernel through 6.1.4 allows attackers to cause a denial of service (slab-out-of-bounds read) because of type confusion (non-negative numbers can sometimes indicate a TC_ACT_SHOT condition rather than valid classification results). (CVE-2023-23454)
- atm_tc_enqueue in net/sched/sch_atm.c in the Linux kernel through 6.1.4 allows attackers to cause a denial of service because of type confusion (non-negative numbers can sometimes indicate a TC_ACT_SHOT condition rather than valid classification results). (CVE-2023-23455)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.
Solution
Run 'yum update kernel' to update your system.
Plugin Details
File Name: al2_ALASKERNEL-5_4-2023-042.nasl
Agent: unix
Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Nessus Agent, Nessus
Risk Information
Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C
Vulnerability Information
CPE: p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:bpftool, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-debuginfo-common-aarch64, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:python-perf-debuginfo, p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:kernel-debuginfo, p-cpe:/a:amazon:linux:kernel-headers, cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:bpftool-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64, p-cpe:/a:amazon:linux:python-perf
Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list
Exploit Ease: Exploits are available
Patch Publication Date: 2/17/2023
Vulnerability Publication Date: 11/28/2022