Ubuntu: Security Advisory (USN-28-1)

# SPDX-FileCopyrightText: 2022 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("1.3.6.1.4.1.25623.1.1.12.2004.28.1");
  script_tag(name:"creation_date", value:"2022-08-26 07:43:23 +0000 (Fri, 26 Aug 2022)");
  script_version("2023-06-21T05:06:22+0000");
  script_tag(name:"last_modification", value:"2023-06-21 05:06:22 +0000 (Wed, 21 Jun 2023)");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:P/I:N/A:N");

  script_name("Ubuntu: Security Advisory (USN-28-1)");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2022 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=UBUNTU4\.10");

  script_xref(name:"Advisory-ID", value:"USN-28-1");
  script_xref(name:"URL", value:"https://ubuntu.com/security/notices/USN-28-1");
  script_xref(name:"URL", value:"http://www.sudo.ws/sudo/alerts/bash_functions.html");

  script_tag(name:"summary", value:"The remote host is missing an update for the 'sudo' package(s) announced via the USN-28-1 advisory.");

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

  script_tag(name:"insight", value:"Liam Helmer discovered an input validation flaw in sudo. When the
standard shell 'bash' starts up, it searches the environment for
variables with a value beginning with '()'. For each of these
variables a function with the same name is created, with the function
body filled in from the environment variable's value.

A malicious user with sudo access to a shell script that uses bash can
use this feature to substitute arbitrary commands for any
non-fully-qualified programs called from the script. Therefore this
flaw can lead to privilege escalation.");

  script_tag(name:"affected", value:"'sudo' package(s) on Ubuntu 4.10.");

  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 == "UBUNTU4.10") {

  if(!isnull(res = isdpkgvuln(pkg:"sudo", ver:"1.6.7p5-1ubuntu4.1", rls:"UBUNTU4.10"))) {
    report += res;
  }

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

exit(0);