Ubuntu: Security Advisory (USN-5072-1)

# SPDX-FileCopyrightText: 2021 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.845053");
  script_cve_id("CVE-2021-3653", "CVE-2021-3656");
  script_tag(name:"creation_date", value:"2021-09-09 01:00:47 +0000 (Thu, 09 Sep 2021)");
  script_version("2024-02-02T05:06:08+0000");
  script_tag(name:"last_modification", value:"2024-02-02 05:06:08 +0000 (Fri, 02 Feb 2024)");
  script_tag(name:"cvss_base", value:"7.2");
  script_tag(name:"cvss_base_vector", value:"AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_tag(name:"severity_vector", value:"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2022-03-10 18:55:35 +0000 (Thu, 10 Mar 2022)");

  script_name("Ubuntu: Security Advisory (USN-5072-1)");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2021 Greenbone AG");
  script_family("Ubuntu Local Security Checks");
  script_dependencies("gather-package-list.nasl");
  script_mandatory_keys("ssh/login/ubuntu_linux", "ssh/login/packages", re:"ssh/login/release=UBUNTU20\.04\ LTS");

  script_xref(name:"Advisory-ID", value:"USN-5072-1");
  script_xref(name:"URL", value:"https://ubuntu.com/security/notices/USN-5072-1");

  script_tag(name:"summary", value:"The remote host is missing an update for the 'linux-azure-5.8, linux-oem-5.10' package(s) announced via the USN-5072-1 advisory.");

  script_tag(name:"vuldetect", value:"Checks if a vulnerable package version is present on the target host.");

  script_tag(name:"insight", value:"Maxim Levitsky and Paolo Bonzini discovered that the KVM hypervisor
implementation for AMD processors in the Linux kernel allowed a guest VM to
disable restrictions on VMLOAD/VMSAVE in a nested guest. An attacker in a
guest VM could use this to read or write portions of the host's physical
memory. (CVE-2021-3656)

Maxim Levitsky discovered that the KVM hypervisor implementation for AMD
processors in the Linux kernel did not properly prevent a guest VM from
enabling AVIC in nested guest VMs. An attacker in a guest VM could use this
to write to portions of the host's physical memory. (CVE-2021-3653)");

  script_tag(name:"affected", value:"'linux-azure-5.8, linux-oem-5.10' package(s) on Ubuntu 20.04.");

  script_tag(name:"solution", value:"Please install the updated package(s).");

  script_tag(name:"solution_type", value:"VendorFix");
  script_tag(name:"qod_type", value:"package");

  exit(0);
}

include("revisions-lib.inc");
include("pkg-lib-deb.inc");

release = dpkg_get_ssh_release();
if(!release)
  exit(0);

res = "";
report = "";

if(release == "UBUNTU20.04 LTS") {

  if(!isnull(res = isdpkgvuln(pkg:"linux-image-5.10.0-1045-oem", ver:"5.10.0-1045.47", rls:"UBUNTU20.04 LTS"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"linux-image-5.8.0-1041-azure", ver:"5.8.0-1041.44~20.04.1", rls:"UBUNTU20.04 LTS"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"linux-image-azure", ver:"5.8.0.1041.44~20.04.13", rls:"UBUNTU20.04 LTS"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"linux-image-oem-20.04", ver:"5.10.0.1045.47", rls:"UBUNTU20.04 LTS"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"linux-image-oem-20.04b", ver:"5.10.0.1045.47", rls:"UBUNTU20.04 LTS"))) {
    report += res;
  }

  if(report != "") {
    security_message(data:report);
  } else if(__pkg_match) {
    exit(99);
  }
  exit(0);
}

exit(0);