Ubuntu 16.04 LTS : Linux kernel (HWE) vulnerabilities (USN-3777-2)

high Nessus Plugin ID 117873

Synopsis

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

Description

The remote Ubuntu 16.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-3777-2 advisory.

- A flaw was found in the way Linux kernel KVM hypervisor before 4.18 emulated instructions such as sgdt/sidt/fxsave/fxrstor. It did not check current privilege(CPL) level while emulating unprivileged instructions. An unprivileged guest user/process could use this flaw to potentially escalate privileges inside guest. (CVE-2018-10853)

- A security flaw was found in the chap_server_compute_md5() function in the ISCSI target code in the Linux kernel in a way an authentication request from an ISCSI initiator is processed. An unauthenticated remote attacker can cause a stack buffer overflow and smash up to 17 bytes of the stack. The attack requires the iSCSI target to be enabled on the victim host. Depending on how the target's code was built (i.e.
depending on a compiler, compile flags and hardware architecture) an attack may lead to a system crash and thus to a denial-of-service or possibly to a non-authorized access to data exported by an iSCSI target.
Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is highly unlikely. Kernel versions 4.18.x, 4.14.x and 3.10.x are believed to be vulnerable. (CVE-2018-14633)

- The spectre_v2_select_mitigation function in arch/x86/kernel/cpu/bugs.c in the Linux kernel before 4.18.1 does not always fill RSB upon a context switch, which makes it easier for attackers to conduct userspace- userspace spectreRSB attacks. (CVE-2018-15572)

- arch/x86/kernel/paravirt.c in the Linux kernel before 4.18.1 mishandles certain indirect calls, which makes it easier for attackers to conduct Spectre-v2 attacks against paravirtual guests. (CVE-2018-15594)

- An issue was discovered in the Linux kernel through 4.18.8. The vmacache_flush_all function in mm/vmacache.c mishandles sequence number overflows. An attacker can trigger a use-after-free (and possibly gain privileges) via certain thread creation, map, unmap, invalidation, and dereference operations.
(CVE-2018-17182)

- Memory leak in the irda_bind function in net/irda/af_irda.c and later in drivers/staging/irda/net/af_irda.c in the Linux kernel before 4.17 allows local users to cause a denial of service (memory consumption) by repeatedly binding an AF_IRDA socket. (CVE-2018-6554)

- The irda_setsockopt function in net/irda/af_irda.c and later in drivers/staging/irda/net/af_irda.c in the Linux kernel before 4.17 allows local users to cause a denial of service (ias_object use-after-free and system crash) or possibly have unspecified other impact via an AF_IRDA socket. (CVE-2018-6555)

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-3777-2

Plugin Details

Severity: High

ID: 117873

File Name: ubuntu_USN-3777-2.nasl

Version: 1.12

Type: local

Agent: unix

Published: 10/2/2018

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: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 8.3

Temporal Score: 6.5

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

CVSS Score Source: CVE-2018-14633

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-2018-6555

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1021-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-36-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-36-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-36-lowlatency, cpe:/o:canonical:ubuntu_linux:16.04:-: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: 10/1/2018

Vulnerability Publication Date: 8/20/2018

Reference Information

CVE: CVE-2018-10853, CVE-2018-14633, CVE-2018-15572, CVE-2018-15594, CVE-2018-17182, CVE-2018-6554, CVE-2018-6555

USN: 3777-2