Ubuntu 16.04 LTS / 18.04 LTS : Linux kernel (Azure, GCP, OEM) vulnerabilities (USN-3752-3)

high Nessus Plugin ID 112189

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 16.04 LTS / 18.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-3752-3 advisory.

- The Linux Kernel versions 4.14, 4.15, and 4.16 has a null pointer dereference which can result in an out of memory (OOM) killing of large mlocked processes. The issue arises from an oom killed process's final thread calling exit_mmap(), which calls munlock_vma_pages_all() for mlocked vmas.This can happen synchronously with the oom reaper's unmap_page_range() since the vma's VM_LOCKED bit is cleared before munlocking (to determine if any other vmas share the memory and are mlocked). (CVE-2018-1000200)

- Linux Kernel version 3.18 to 4.16 incorrectly handles an SG_IO ioctl on /dev/sg0 with dxfer_direction=SG_DXFER_FROM_DEV and an empty 6-byte cmdp. This may lead to copying up to 1000 kernel heap pages to the userspace. This has been fixed upstream in https://github.com/torvalds/linux/commit/a45b599ad808c3c982fdcdc12b0b8611c2f92824 already. The problem has limited scope, as users don't usually have permissions to access SCSI devices. On the other hand, e.g. the Nero user manual suggests doing `chmod o+r+w /dev/sg*` to make the devices accessible. NOTE: third parties dispute the relevance of this report, noting that the requirement for an attacker to have both the CAP_SYS_ADMIN and CAP_SYS_RAWIO capabilities makes it virtually impossible to exploit. (CVE-2018-1000204)

- The xfs_bmap_extents_to_btree function in fs/xfs/libxfs/xfs_bmap.c in the Linux kernel through 4.16.3 allows local users to cause a denial of service (xfs_bmapi_write NULL pointer dereference) via a crafted xfs image. (CVE-2018-10323)

- Linux kernel is vulnerable to a heap-based buffer overflow in the fs/ext4/xattr.c:ext4_xattr_set_entry() function. An attacker could exploit this by operating on a mounted crafted ext4 image. (CVE-2018-10840)

- A flaw was found in the Linux kernel's ext4 filesystem. A local user can cause an out-of-bound access in ext4_get_group_info function, a denial of service, and a system crash by mounting and operating on a crafted ext4 filesystem image. (CVE-2018-10881)

- The ext4_valid_block_bitmap function in fs/ext4/balloc.c in the Linux kernel through 4.15.15 allows attackers to cause a denial of service (out-of-bounds read and system crash) via a crafted ext4 image because balloc.c and ialloc.c do not validate bitmap block numbers. (CVE-2018-1093)

- kernel drivers before version 4.17-rc1 are vulnerable to a weakness in the Linux kernel's implementation of random seed data. Programs, early in the boot sequence, could use the data allocated for the seed before it was sufficiently generated. (CVE-2018-1108)

- A flaw was found affecting the Linux kernel before version 4.17. By mmap()ing a FUSE-backed file onto a process's memory containing command line arguments (or environment strings), an attacker can cause utilities from psutils or procps (such as ps, w) or any other program which makes a read() call to the /proc/<pid>/cmdline (or /proc/<pid>/environ) files to block indefinitely (denial of service) or for some controlled time (as a synchronization primitive for other attacks). (CVE-2018-1120)

- In the Linux kernel 4.13 through 4.16.11, ext4_read_inline_data() in fs/ext4/inline.c performs a memcpy with an untrusted length value in certain circumstances involving a crafted filesystem that stores the system.data extended attribute value in a dedicated inode. (CVE-2018-11412)

- The sr_do_ioctl function in drivers/scsi/sr_ioctl.c in the Linux kernel through 4.16.12 allows local users to cause a denial of service (stack-based buffer overflow) or possibly have unspecified other impact because sense buffers have different sizes at the CDROM layer and the SCSI layer, as demonstrated by a CDROMREADMODE2 ioctl call. (CVE-2018-11506)

- In net/socket.c in the Linux kernel through 4.17.1, there is a race condition between fchownat and close in cases where they target the same socket file descriptor, related to the sock_close and sockfs_setattr functions. fchownat does not increment the file descriptor reference count, which allows close to set the socket to NULL during fchownat's execution, leading to a NULL pointer dereference and system crash.
(CVE-2018-12232)

- In the ea_get function in fs/jfs/xattr.c in the Linux kernel through 4.17.1, a memory corruption bug in JFS can be triggered by calling setxattr twice with two different extended attribute names on the same file. This vulnerability can be triggered by an unprivileged user with the ability to create files and execute programs. A kmalloc call is incorrect, leading to slab-out-of-bounds in jfs_xattr.
(CVE-2018-12233)

- In arch/x86/kvm/vmx.c in the Linux kernel before 4.17.2, when nested virtualization is used, local attackers could cause L1 KVM guests to VMEXIT, potentially allowing privilege escalations and denial of service attacks due to lack of checking of CPL. (CVE-2018-12904)

- An issue was discovered in fs/xfs/libxfs/xfs_attr_leaf.c in the Linux kernel through 4.17.3. An OOPS may occur for a corrupted xfs image after xfs_da_shrink_inode() is called with a NULL bp. (CVE-2018-13094)

- The inode_init_owner function in fs/inode.c in the Linux kernel through 3.16 allows local users to create files with an unintended group ownership, in a scenario where a directory is SGID to a certain group and is writable by a user who is not a member of that group. Here, the non-member can trigger creation of a plain file whose group ownership is that group. The intended behavior was that the non-member can trigger creation of a directory (but not a plain file) whose group ownership is that group. The non-member can escalate privileges by making the plain file executable and SGID. (CVE-2018-13405)

- An integer overflow in the uvesafb_setcmap function in drivers/video/fbdev/uvesafb.c in the Linux kernel before 4.17.4 could result in local attackers being able to crash the kernel or potentially elevate privileges because kmalloc_array is not used. (CVE-2018-13406)

- In the Linux Kernel before version 4.16.11, 4.14.43, 4.9.102, and 4.4.133, multiple race condition errors when handling probe, disconnect, and rebind operations can be exploited to trigger a use-after-free condition or a NULL pointer dereference by sending multiple USB over IP packets. (CVE-2018-5814)

- In driver_override_store and driver_override_show of bus.c, there is a possible double free due to improper locking. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Product: Android Versions: Android kernel Android ID: A-69129004 References: Upstream kernel. (CVE-2018-9415)

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

Solution

Update the affected kernel package.

See Also

https://ubuntu.com/security/notices/USN-3752-3

Plugin Details

Severity: High

ID: 112189

File Name: ubuntu_USN-3752-3.nasl

Version: 1.11

Type: local

Agent: unix

Published: 8/30/2018

Updated: 1/9/2024

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2018-13406

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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

CVSS Score Source: CVE-2018-9415

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1017-oem, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1018-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1022-azure, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts

Required KB Items: Host/cpu, Host/Debian/dpkg-l, Host/Ubuntu, Host/Ubuntu/release

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 8/28/2018

Vulnerability Publication Date: 4/2/2018

Reference Information

CVE: CVE-2018-1000200, CVE-2018-1000204, CVE-2018-10323, CVE-2018-10840, CVE-2018-10881, CVE-2018-1093, CVE-2018-1108, CVE-2018-1120, CVE-2018-11412, CVE-2018-11506, CVE-2018-12232, CVE-2018-12233, CVE-2018-12904, CVE-2018-13094, CVE-2018-13405, CVE-2018-13406, CVE-2018-5814, CVE-2018-9415

USN: 3752-3