Debian: Security Advisory (DLA-1617-1)

# SPDX-FileCopyrightText: 2018 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("1.3.6.1.4.1.25623.1.0.891617");
  script_cve_id("CVE-2018-15127", "CVE-2018-20019", "CVE-2018-20020", "CVE-2018-20021", "CVE-2018-20022", "CVE-2018-20023", "CVE-2018-20024", "CVE-2018-21247", "CVE-2018-6307");
  script_tag(name:"creation_date", value:"2018-12-27 23:00:00 +0000 (Thu, 27 Dec 2018)");
  script_version("2024-02-02T05:06:06+0000");
  script_tag(name:"last_modification", value:"2024-02-02 05:06:06 +0000 (Fri, 02 Feb 2024)");
  script_tag(name:"cvss_base", value:"7.8");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:N/A:C");
  script_tag(name:"severity_vector", value:"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2019-01-07 21:11:03 +0000 (Mon, 07 Jan 2019)");

  script_name("Debian: Security Advisory (DLA-1617-1)");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2018 Greenbone AG");
  script_family("Debian Local Security Checks");
  script_dependencies("gather-package-list.nasl");
  script_mandatory_keys("ssh/login/debian_linux", "ssh/login/packages", re:"ssh/login/release=DEB8");

  script_xref(name:"Advisory-ID", value:"DLA-1617-1");
  script_xref(name:"URL", value:"https://www.debian.org/lts/security/2018/DLA-1617-1");
  script_xref(name:"URL", value:"https://wiki.debian.org/LTS");

  script_tag(name:"summary", value:"The remote host is missing an update for the Debian 'libvncserver' package(s) announced via the DLA-1617-1 advisory.");

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

  script_tag(name:"insight", value:"Kaspersky Lab discovered several vulnerabilities in libvncserver, a C library to implement VNC server/client functionalities.

CVE-2018-6307

a heap use-after-free vulnerability in the server code of the file transfer extension, which can result in remote code execution. This attack appears to be exploitable via network connectivity.

CVE-2018-15127

contains a heap out-of-bound write vulnerability in the server code of the file transfer extension, which can result in remote code execution. This attack appears to be exploitable via network connectivity.

CVE-2018-20019

multiple heap out-of-bound write vulnerabilities in VNC client code, which can result in remote code execution.

CVE-2018-20020

heap out-of-bound write vulnerability in a structure in VNC client code, which can result in remote code execution.

CVE-2018-20021

CWE-835: Infinite Loop vulnerability in VNC client code. The vulnerability could allow an attacker to consume an excessive amount of resources, such as CPU and RAM.

CVE-2018-20022

CWE-665: Improper Initialization weaknesses in VNC client code, which could allow an attacker to read stack memory and can be abused for information disclosure. Combined with another vulnerability, it can be used to leak stack memory layout and bypass ASLR.

CVE-2018-20023

Improper Initialization vulnerability in VNC Repeater client code, which could allow an attacker to read stack memory and can be abused for information disclosure. Combined with another vulnerability, it can be used to leak stack memory layout and bypass ASLR.

CVE-2018-20024

a null pointer dereference in VNC client code, which can result in DoS.

For Debian 8 Jessie, these problems have been fixed in version 0.9.9+dfsg2-6.1+deb8u4.

We recommend that you upgrade your libvncserver packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: [link moved to references]");

  script_tag(name:"affected", value:"'libvncserver' package(s) on Debian 8.");

  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 == "DEB8") {

  if(!isnull(res = isdpkgvuln(pkg:"libvncclient0", ver:"0.9.9+dfsg2-6.1+deb8u4", rls:"DEB8"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"libvncclient0-dbg", ver:"0.9.9+dfsg2-6.1+deb8u4", rls:"DEB8"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"libvncserver-config", ver:"0.9.9+dfsg2-6.1+deb8u4", rls:"DEB8"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"libvncserver-dev", ver:"0.9.9+dfsg2-6.1+deb8u4", rls:"DEB8"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"libvncserver0", ver:"0.9.9+dfsg2-6.1+deb8u4", rls:"DEB8"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"libvncserver0-dbg", ver:"0.9.9+dfsg2-6.1+deb8u4", rls:"DEB8"))) {
    report += res;
  }

  if(!isnull(res = isdpkgvuln(pkg:"linuxvnc", ver:"0.9.9+dfsg2-6.1+deb8u4", rls:"DEB8"))) {
    report += res;
  }

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

exit(0);